Guidance on Applying WCAG 2 to Non-Web Information and Communications Technologies (WCAG2ICT)

W3C Editor's Draft

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Abstract

This document, “Guidance on Applying WCAG 2 to Non-Web Information and Communications Technologies (WCAG2ICT)” describes how the Web Content Accessibility Guidelines (WCAG) versions 2.0 [WCAG20], 2.1 [WCAG21], and 2.2 [WCAG22] principles, guidelines, and success criteria can be applied to non-web Information and Communications Technologies (ICT), specifically to non-web documents and software. It provides informative guidance (guidance that is not normative and does not set requirements).

This document is part of a series of technical and educational documents published by the W3C Web Accessibility Initiative (WAI) and available from the WCAG2ICT Overview.

Status of This Document

This section describes the status of this document at the time of its publication. A list of current W3C publications and the latest revision of this technical report can be found in the W3C technical reports index at https://www.w3.org/TR/.

This is a Technical Report on Applying WCAG 2 to Non-Web Information and Communications Technologies (WCAG2ICT). The purpose of this work is to update the 2013 WCAG2ICT Note's guidance to include changes made in WCAG 2.1 and 2.2.

Editor's note

The current draft includes guidance for all of the WCAG 2 success criteria from WCAG 2.0, 2.1, and 2.2.

The group is seeking feedback on the following aspects that were added or have substantial changes in this draft:

This is the planned last draft before we publish this as a W3C Working Group Note.

This document was published by the Accessibility Guidelines Working Group as an Editor's Draft.

Publication as an Editor's Draft does not imply endorsement by W3C and its Members.

This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.

This document was produced by a group operating under the W3C Patent Policy. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.

This document is governed by the 03 November 2023 W3C Process Document.

Introduction

Background

This document is an update to a W3C Working Group Note to incorporate new guidelines, success criteria, and definitions added in WCAG 2.1 and 2.2.

Guidance on Applying WCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT), approved in September 2013, described how WCAG 2.0 could be applied to non-web documents and software. WCAG2ICT was organized to mirror WCAG's sections: Perceivable, Operable, Understandable, and Robust. WCAG2ICT clarified when and how WCAG success criteria should be applied to non-web documents and software. Some were applicable without modification and some were applicable with edits and/or notes. Glossary terms were also reviewed. Level AAA success criteria were not addressed in the 2013 WCAG2ICT Working Group Note.

The 2013 WCAG2ICT has been relied upon in regulations and legislation. One example is [etsi-en-301-549] (Europe) and other standards that reference or incorporate EN 301 549 (e.g., India, Kenya, Australia). Another example is Section 508 (U.S.) Application of WCAG 2.0 to Non-Web ICT, which looked to WCAG2ICT for detailed direction with providing specific guidance and exceptions to particular criteria from being applied to non-web technology. Section 508 incorporated by reference WCAG as the Accessibility Standard applicable to non-web documents and requires WCAG Conformance for non-web software.

Guidance in this Document

This document provides informative guidance (guidance that is not normative and that does not set requirements) with regard to the interpretation and application of Web Content Accessibility Guidelines (WCAG) to non-web information and communications technologies (ICT). This document is a Working Group Note (in contrast to WCAG 2.0, WCAG 2.1, and WCAG 2.2, which are W3C Recommendations). Specifically, this document provides informative guidance on applying WCAG 2.0, 2.1, and 2.2 Level A and AA success criteria to non-web ICT, specifically to non-web documents and software.

Note 1
Hereafter, the use of WCAG 2 means all WCAG 2.x versions — 2.0, 2.1, and 2.2.

This document is intended to help clarify how to use WCAG 2 to make non-web documents and software more accessible to people with disabilities. Addressing accessibility involves addressing the needs of people with auditory, cognitive, neurological, physical, speech, and visual impairments, as well as accessibility needs of people due to the effects of aging.

Although this document covers a wide range of issues, it is not able to address all the needs of all people with disabilities. Since WCAG 2 was developed for the Web, addressing accessibility for non-web documents and software may involve requirements and considerations beyond those included in this document. Authors and developers are encouraged to seek relevant advice about current best practices to ensure that non-web documents and software are accessible, as much as possible, to people with disabilities. The following WCAG 2 supporting documents, though they have not been changed to fully apply in non-web contexts, contain helpful information to learn about the user needs, intent, and generalized implementation techniques:

While WCAG 2 was designed to be technology-neutral, it assumes the presence of a “user agent” such as a browser, media player, or assistive technology as a means to access web content. Therefore, the application of WCAG 2 to documents and software in non-web contexts necessitates some interpretation in order to determine how the intent of each WCAG 2 success criterion could be met in these different contexts of use. Therefore, the bulk of the Task Force's work involved evaluating how each WCAG 2 success criterion would apply in the context of non-web ICT, if it were applied to non-web ICT.

The Task Force found that the majority of success criteria from WCAG 2 can be applied to non-web documents and software with either no or minimal changes. Since many of the Level A and AA success criteria do not include any web-related terms, they apply directly as written and as described in the “Intent” sections from the Understanding WCAG 2.2 [UNDERSTANDING-WCAG22] resource. Additional notes were provided, as needed, to provide assistance in applying them to non-web documents and software.

Interpretation of Web Terminology in a Non-web Context

When certain Web-specific terms or phrases like “web page(s)” were used in success criteria, those were replaced with non-web terms or phrases like “non-web document(s) and software”. Additional notes were also provided to explain the terminology replacements.

A small number of success criteria are written to apply to “a set of web pages” or “multiple web pages” and depend upon all pages in the set to share some characteristic or behavior. Since the unit of conformance in WCAG 2 is a single web page, the task force agreed that the equivalent unit of conformance for non-web documents is a single document. It follows that an equivalent unit of evaluation for a “set of web pages” would be a ”set of documents”. Since it isn't possible to unambiguously carve up non-web software into discrete pieces, a single “web page” was equated to a “software program” and a “set of web pages” was equated to a “set of software programs.  Both of these terms are defined in the Key Terms section of this document. See “set of documents” and “set of software programs” to determine when a group of documents or pieces of software are considered a set.

Note
Sets of software that meet this definition appear to be extremely rare.

Not all success criteria have been fully adopted in all local regulations and legislation, and may not be applicable to all technologies. WCAG2ICT has been used in some regulations to determine whether or not to apply certain success criteria. For example, some local standards such as Section 508 in the US, and EN 301 549 in Europe, state that WCAG 2.0 Success Criteria 2.4.1 Bypass Blocks, 2.4.5 Multiple Ways, 3.2.3 Consistent Navigation, and 3.2.4 Consistent Identification do not apply to non-Web documents and non-Web software. In addition, EN 301 549 also states that 2.4.2 Page titled and 3.1.2 Language of parts does not apply to non-Web software. In contrast, the U.S. Department of Justice regulation Nondiscrimination on the Basis of Disability; Accessibility of Web Information and Services of State and Local Government Entities (89 FR 31320, 24 April 2024) directs implementers to utilize the guidance in this document to determine the applicability and how to apply the requirements to mobile applications. Since this document does not specifically say which criteria can or should apply, those implementing this document (WCAG2ICT) should consider the applicability of individual success criteria to non-web documents and software.

The glossary terms were also reviewed and most of them applied to non-Web documents and software, as written. Some applied with additional notes or edits (largely related to phrases like “Web page(s)”), and a small number of terms were only used in Level AAA success criteria which are not addressed by the WCAG2ICT Note at this time.

Excluded from Scope

The following are out of scope for this document:

Document Overview

This document includes text quoted from the WCAG 2.2 principles, guidelines, success criteria, and glossary definitions without any changes. The guidance provided by this document for each principle, guideline, success criterion, and definition is preceded by a heading beginning with “Applying…”. This guidance was created by the WCAG2ICT Task Force, then reviewed and approved by the Accessibility Guidelines Working Group.

Document Conventions

The following stylistic conventions are used in this document:

Comparison with the 2013 WCAG2ICT Note

Editor's note

The WCAG2ICT Task Force has incorporated all of the new WCAG 2.1 and WCAG 2.2 guidelines, criteria and glossary terms, and addressed all open issues on content in the previous draft of the document.

The following changes and additions have been made to update the 2013 WCAG2ICT document to incorporate the new features in WCAG 2.1, the new features in WCAG 2.2, and the change to 4.1.1 Parsing listed in the Comparison with WCAG 2.1 section:

Key Terms

Editor's note

This draft of WCAG2ICT introduced two new key terms: closed functionality and menu driven interface.

WCAG2ICT provides some key glossary terms to address differences between web and non-web contexts and to introduce terms that are nonexistent in WCAG but important to define for a non-web context. “Content” and “user agent” are glossary terms from WCAG 2 that need to be interpreted significantly differently when applied to non-web ICT. The glossary term “Web page” in WCAG 2 is replaced with the defined terms “document” and “software”, and both “set of web pages” and “multiple web pages” are replaced with the defined terms “set of documents” and “set of software programs”. The terms introduced by WCAG2ICT are “accessibility services of platform software” because non-Web software doesn't leverage the WCAG notion of a user agent, and "closed functionality" which is specific to non-web software. The remaining glossary terms from WCAG 2 are addressed in Chapter 7 Comments on Definitions in WCAG 2 Glossary. Terms defined and used in WCAG2ICT are applicable only to the interpretation of the guidance in this document. The particular definitions should not be interpreted as having applicability to situations beyond the scope of WCAG2ICT. Further information on usage of these terms follows.

Accessibility Services of Platform Software

The term accessibility services of platform software, as used in WCAG2ICT, has the meaning below:

accessibility services of platform software (as used in WCAG2ICT)

services provided by an operating system, user agent, or other platform software that enable non-web documents or software to expose information about the user interface and events to assistive technologies and accessibility features of software

Note

These services are commonly provided in the form of accessibility APIs (application programming interfaces), and they provide two-way communication with assistive technologies, including exposing information about objects and events.

Closed Functionality

The term closed functionality, as used in WCAG2ICT, has the meaning below:

closed functionality (as used in WCAG2ICT)

a property or characteristic that prevents users from attaching, installing, or using assistive technology

Note

To support users with disabilities, products with closed functionality might instead provide built-in features that function as assistive technology or use other mechanisms to make the technology accessible.

Example: Examples of technology with closed functionality include:

  • self-service transaction machines or kiosks — examples include machines used for retail self-checkout, point of sales (POS) terminals, ticketing and self-check-in, and Automated Teller Machines (ATMs).
  • telephony devices such as IP phones, feature phones, smartphones, and phone-enabled tablets (although such devices are becoming increasingly open and/or supplying AT and accessibility features that software can rely upon to meet WCAG requirements.)
  • entertainment technologies including smart TVs, set-top boxes, smart displays, smart speakers, smart watches, and tablets
  • an ebook reader or standalone ebook software that allows assistive technologies to access all of the user interface controls of the ebook program (open functionality) but does not allow the assistive technologies to access the actual content of book (closed functionality).
  • an operating system that makes the user provide login credentials before it allows any assistive technologies to be loaded. The login portion would be closed functionality.
  • other technology devices, such as printers, displays, and Internet of Things (IoT) devices.

These examples are explained more fully in the Comments on Closed Functionality section.

Content (on and off the Web)

WCAG 2 defines content as:

information and sensory experience to be communicated to the user by means of a user agent, including code or markup that defines the content's structure, presentation, and interactions

For non-web content it is necessary to view this a bit more broadly. Within WCAG2ICT, the term “content” is used as follows:

content (non-web content) (as used in WCAG2ICT)

information and sensory experience to be communicated to the user by means of [software], including code or markup that defines the content's structure, presentation, and interactions

Note

Non-web content occurs in two places; documents and software. When content occurs in a document, a user agent is needed in order to communicate the content's information and sensory experience to the user. When content occurs in software, a separate user agent isn't needed — the software itself performs that function.

Within WCAG2ICT wherever “content” or “web content” appears in a success criterion it is replaced with “content” using the definition above.

Document

The term document, as used in WCAG2ICT, has the meaning below:

document (as used in WCAG2ICT)

assembly of content, such as a file, set of files, or streamed media that functions as a single item rather than a collection, that is not part of software and that does not include its own user agent

Note 1

A document always depends upon a user agent to present its content to the user.

Note 2

Letters, spreadsheets, emails, books, pictures, presentations, and movies are examples of documents.

Note 3

Software configuration and storage files such as databases and virus definitions, as well as computer instruction files such as source code, batch/script files, and firmware, are examples of files that function as part of software and thus are not examples of documents. If and where software retrieves “information and sensory experience to be communicated to the user” from such files, it is just another part of the content that occurs in software and is covered by WCAG2ICT like any other parts of the software. Where such files contain one or more embedded documents, the embedded documents remain documents under this definition.

Note 4

A collection of files zipped together into an archive, stored within a single virtual hard drive file, or stored in a single "encrypted file system" file, do not constitute a single document.

Note 5

Anything that can present its own content without involving a user agent, such as a self-playing book, is not a document but is software.

Note 6

A single document may be composed of multiple files such as the video content, closed caption text, etc. This fact is not usually apparent to the end-user consuming the document / content. This is similar to how a single web page can be composed of content from multiple URIs (e.g. the page text, images, the JavaScript, a CSS file etc.).

Example: An assembly of files that represented the video, audio, captions, and timing files for a movie would be a document.

Counterexample: A binder file used to bind together the various exhibits for a legal case would not be a document.

Set of Documents

The term set of documents, as used in WCAG2ICT, has the meaning below:

set of documents (non-web) (as used in WCAG2ICT)

collection of [documents] that share a common purpose, are created by the same author, group or organization [and that are published together, and the documents all refer to each other by name or link]

Note 1

Republishing or bundling previously published documents as a collection does not constitute a set of documents.

Note 2

If a set is broken apart, the individual parts are no longer part of a set, and would be evaluated as any other individual document is evaluated.

Example: One example of a set of documents would be a three-part report where each part is a separate file. The table of contents is repeated at the beginning of each file to enable navigation to the other parts.

Set of Software Programs

The term set of software programs, as used in WCAG2ICT, has the meaning below:

set of software programs (as used in WCAG2ICT)

collection of [software programs] that share a common purpose, are created by the same author, group or organization [and that are distributed together and can be launched and used independently from each other, but are interlinked each with every other one such that users can navigate from one program to another via a consistent method that appears in each member of the set]

Note 1

Although "sets of web pages" occur frequently, "sets of software programs" appear to be extremely rare.

Note 2

Redistributing or bundling previously distributed software as a collection does not constitute a set of software programs.

Note 3

Consistent does not mean identical. For example, if a list of choices is provided it might not include the name of the current program.

Note 4

If a member of the set is separated from the set, it is no longer part of a set, and would be evaluated as any other individual software program.

Note 5

Any software program that is not part of a set, per this definition, would automatically satisfy any success criterion that is specified to apply to “sets of” software (as is true for any success criterion that is scoped to only apply to some other type of content).

Note 6

If there is any ambiguity whether the group is a set, then the group is not a set.

Note 7

If there is no independent method to launch the software programs (as is common in closed products), those programs would not meet the definition of a "set of software programs".

Note 8

Although the term “software” is used throughout this document because this would apply to stand-alone software programs as well as individual software components and the software components in software-hardware combinations, the concept of “set of software programs” would only apply (by definition) to programs that can be launched separately from each other. Therefore, in the WCAG2ICT guidance for the provisions that use the phrase “set of” (Success Criteria 2.4.1, 2.4.5, 3.2.3, 3.2.4, and 3.2.6), the phrase “set of software programs” is used.

Example: One example of a set of software programs would be a group of programs that can be launched and used separately but are distributed together and all have a menu that allows users to launch, or switch to, each of the other programs in the group.

Counterexamples: Examples of things that are not sets of software programs:

  • A suite of programs for authoring different types of documents (text, spreadsheets, presentations, etc.) where the programs don't provide an explicit, consistent means to launch, or switch to, each of the other programs in the group.
  • An office package consisting of multiple programs that launches as a single program that provides multiple functionalities such as writing, spreadsheet, etc., but the only way to navigate between programs is to open a document in one of the programs.
  • A bundle of software programs that is sold together but the only way to navigate between the programs in the bundle is to use a platform software level menu to navigate between them (and not via a menu provided by each program that allows you to navigate to just the other programs in this bundle).
  • A group of programs that was a set, but the programs have been moved to separate locations so that their “set” behaviors were disrupted and no longer work. Even though they were a set at one time, because they are no longer installed as a set they no longer are a set and would not need to meet any success criteria that apply to sets of software.

Software

The term software as used in WCAG2ICT, has the meaning below:

software (as used in WCAG2ICT)

software, products or software aspects of hardware-software products, that have a user interface and do not depend upon a separate user agent to present any of its content

Note 1

For software, the user interface and any other embedded content is covered by these guidelines. The software provides a function equivalent to a user agent for the embedded content.

Note 2

Software without a user interface does not have content and is not covered by these guidelines. For example, driver software with no user interface would not be covered.

Note 3

Because software with a user interface provides a function equivalent to a user agent in addition to content, the application of some WCAG 2 success criteria would be different for content embedded in software versus content in a document, where it is viewed through a separate user agent (e.g. browser, player, viewer, etc.).

User Agent

WCAG 2 defines user agent as:

user agent

any software that retrieves and presents Web content for users

Example: Web browsers, media players, plug-ins, and other programs—including assistive technologies—that help in retrieving, rendering, and interacting with Web content.

For non-web ICT, “user agent” needs to be viewed differently. In WCAG 2, the term “user agent” only refers to retrieval and display of web content. For non-web ICT, the term “user agent” refers to retrieval and display of separate content that is not on the Web, which WCAG2ICT refers to as a “document”. Within WCAG2ICT, the term “user agent” is used as follows:

user agent (as used in WCAG2ICT)

any software that retrieves and presents [documents] for users

Note 1

Software that only displays the content contained within it is not considered to be a user agent. It is just considered to be software.

Note 2

An example of software that is not a user agent is a calculator application that doesn't retrieve the calculations from outside the software to present it to a user. In this case, the calculator software is not a user agent, it is simply software with a user interface.

Note 3

Software that only shows a preview of content such as a thumbnail or other non-fully functioning presentation is not providing user agent functionality.

Comments on Closed Functionality

Editor's note

This section has been updated to address public comments received on the previous draft. In addition, Appendix A: Success Criteria Problematic for Closed Functionality has been updated to include new WCAG 2.1 and 2.2 criteria that are problematic for Closed Functionality.

As noted in the Introduction, WCAG 2 assumes the presence of a “user agent” such as a browser, media player, or assistive technology as a means to access web content. Many of the success criteria in WCAG 2 assume web content will be accessed by ICT where assistive technologies can be connected to it or installed on it. The assistive technologies then present the web content to people with disabilities in an accessible form.

ICT with closed functionality does not allow the use of some assistive technologies for some or all of the ICT's functions. In many cases, such ICT also lacks a “user agent” or its equivalent. To the extent the ICT is closed, following the WCAG success criteria by themselves will not ensure that non-web software is accessible. Where assistive technologies or user agents are not available to address the intent of these success criteria, something else needs to be provided or be required to facilitate accessibility as intended by WCAG 2. It is outside the WCAG2ICT Task Force Work Statement to say what additional measures are needed, but WCAG2ICT points out which success criteria depend on assistive technologies — and therefore which success criteria would be problematic in the context of ICT with closed functionality.

Example: In developing guidance for closed functionality, the task force has considered examples of ICT that historically have been partially or fully closed to assistive technologies:

There are existing standards that provide accessibility requirements for both hardware and software aspects of ICT with closed functionality. This document does not comment on those standards, but does note that WCAG success criteria should not be applied to hardware aspects of ICT with closed functionality. WCAG2ICT does provide considerations for applying WCAG success criteria to software on ICT with closed functionality. WCAG2ICT also indicates where and why success criteria might be problematic for non-web software due to the underlying assumptions built into the WCAG success criteria. See Appendix A: Success Criteria Problematic for Closed Functionality for a list of success criteria for which this is relevant.

Text / Command-line / Terminal Applications and Interfaces

Text applications are a class of software ICT that appeared decades ago, prior to the emergence of the graphical user interface (GUI) and the Web. The interface of a text application is generated using only text characters, and either a hardware terminal or a software terminal application handles the rendering of the text application—similar to how a web user agent handles the rendering of a web application. Text applications only accept text input, though some may also support the use of a mouse or other input devices. More recently, terminal applications that render text applications in the GUI may utilize spoken input through Automated Speech Recognition (ASR). Both GUI and native text environment interfaces also now commonly support word-completion prediction technologies. Command-line applications are a subset of text applications with further specific properties.

Historically, assistive technologies developed alongside text applications, making it possible for text applications to be accessible. Although there are far fewer new text applications being developed compared to new GUI or web applications, text applications remain in use today. In fact, command-line interfaces have seen a resurgence in recent years, especially in popular programming and revision-tracking environments with continued development and greater functionality. In some cases this has precipitated renewed developments in assistive technology support for text applications.

Assistive technology support continues to evolve in today's text applications. Key examples include:

As noted in Appendix B. Background on Text / Command-line / Terminal Applications and Interfaces, applying WCAG to text / command-line applications involves understanding how text applications are rendered, how text applications have been made accessible via assistive technologies, and how to apply the concepts of “accessibility supported” and “programmatically determined” to text applications.

Comments on Conformance

WCAG2ICT is not a standard, so it is not possible to conform to WCAG2ICT. However, some entities may wish to use the information in WCAG2ICT to help establish standards or regulations regarding accessibility in ICT that are based on WCAG 2. While such standards or regulations will need to address matters of conformance themselves, the following notes may be of assistance to those wishing to apply WCAG 2 to non-web documents and software:

  1. The WCAG 2 success criteria and the conformance requirements were designed to work together, such that the language of the success criteria is based on the nature of the conformance requirements. The choice of what level to use for a given criteria (A vs. AA vs. AAA) was further influenced by a number of factors specific to the web domain, as set forth in Understanding Levels of Conformance.
  2. In the WCAG 2 conformance model, a success criterion is satisfied if the item being evaluated does not fail it. If the success criterion is in relation to something that does not exist for the item being evaluated (e.g. a success criterion is about captioning audio and there is no audio), where some might consider the criterion "not applicable", the success criterion is automatically met. This approach is central to the way the success criteria in WCAG are structured and worded.
  3. WCAG 2 conformance is applied to the item being evaluated (i.e. web page) as a whole, except when a process includes use of several items, in which case all of the items that are needed in order to complete the process must conform.
  4. In WCAG 2, when conformance depends upon accessibility features of the platform (i.e. browser for web content) or on assistive technologies, WCAG 2 requires that there are assistive technologies, etc. that work with the product (web page). That is, conformance with WCAG 2 requires that only accessibility-supported ways of using technologies are relied upon to satisfy the success criteria.
  5. WCAG 2 allows information on part of a page to not conform if the same information is available elsewhere on the page in a conforming fashion. However, WCAG 2 identifies four success criteria that must be met on all areas of the page because they can interfere with the user's ability to access and use other parts of the page:

Also, as noted in the Introduction, it wasn't possible to unambiguously carve up software into discrete pieces, and so the unit of evaluation for non-web software is the whole software program. As with any software testing, this can be a very large unit of evaluation, and methods similar to standard software testing may be needed.

Comments by Guideline and Success Criterion

Editor's note
The WCAG2ICT Task Force has incorporated all of the new WCAG 2.1 and WCAG 2.2 guidelines, success criteria, and glossary terms into this draft. The Task Force also made changes to address public comments.

The sections that follow are organized according to the principles, guidelines, and success criteria from WCAG 2. The text of each success criterion from WCAG 2 is copied as quoted text. Following that, the WCAG2ICT guidance is provided. The WCAG2ICT guidance can be found in the sections where the headings begin with "Applying..." to highlight that this is the content specific to this document.

1. Perceivable

Information and user interface components must be presentable to users in ways they can perceive.

Applying Principle 1 Perceivable to Non-Web Documents and Software

In WCAG 2, the Principles are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Principle 1 applies directly as written.

1.1 Text Alternatives

Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.

Applying Guideline 1.1 Text Alternatives to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 1.1 applies directly as written.

1.1.1 Non-text Content

All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below.

Controls, Input

If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Success Criterion 4.1.2 for additional requirements for controls and content that accepts user input.)

Time-Based Media

If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.)

Test

If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content.

Sensory

If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content.

CAPTCHA

If the purpose of non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities.

Decoration, Formatting, Invisible

If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.

Applying SC 1.1.1 Non-text Content to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.1.1.

Note 1

CAPTCHAs do not currently appear outside of the Web. However, if they do appear, this guidance is accurate.

1.2 Time-based Media

Provide alternatives for time-based media.

Applying Guideline 1.2 Time Based Media to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 1.2 applies directly as written.

1.2.1 Audio-only and Video-only (Prerecorded)

For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such:

Prerecorded Audio-only

An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content.

Prerecorded Video-only

Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.

Applying SC 1.2.1 Audio-only and Video-only (Prerecorded) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.2.1.

Note 1

The alternative can be provided directly in the non-web document or software – or provided in an alternate version that meets the success criteria.

1.2.2 Captions (Prerecorded)

Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Applying SC 1.2.2 Captions (Prerecorded) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.2.2.

Note

The WCAG 2 definition of “captions” notes that “in some countries, captions are called subtitles”. They are also sometimes referred to as “subtitles for the hearing impaired.” Per the definition in WCAG 2, to meet this success criterion, whether called captions or subtitles, they would have to provide “synchronized visual and / or text alternative for both speech and non-speech audio information needed to understand the media content” where non-speech information includes “sound effects, music, laughter, speaker identification and location”.

1.2.3 Audio Description or Media Alternative (Prerecorded)

An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such.

Applying SC 1.2.3 Audio Description or Media Alternative (Prerecorded) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.2.3.

Note 1

The WCAG 2 definition of “audio description” says that “audio description” is “also called ‘video description’ and ‘descriptive narration’”.

Note 2

Secondary or alternate audio tracks are commonly used for this purpose.

1.2.4 Captions (Live)

Captions are provided for all live audio content in synchronized media.

Applying SC 1.2.4 Captions (Live) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.2.4.

Note

The WCAG 2 definition of “captions” notes that “In some countries, captions are called subtitles”. They are also sometimes referred to as “subtitles for the hearing impaired.” Per the definition in WCAG 2, to meet this success criterion, whether called captions or subtitles, they would have to provide “synchronized visual and / or text alternative for both speech and non-speech audio information needed to understand the media content” where non-speech information includes “sound effects, music, laughter, speaker identification and location”.

1.2.5 Audio Description (Prerecorded)

Audio description is provided for all prerecorded video content in synchronized media.

Applying SC 1.2.5 Audio Description (Prerecorded) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.2.5.

Note 1

The WCAG 2 definition of “audio description” says that audio description is “also called ‘video description’ and ‘descriptive narration’”.

Note 2

Secondary or alternate audio tracks are commonly used for this purpose.

1.3 Adaptable

Create content that can be presented in different ways (for example simpler layout) without losing information or structure.

Applying Guideline 1.3 Adaptable to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 1.3 applies directly as written.

1.3.1 Info and Relationships

Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text.

Applying SC 1.3.1 Info and Relationships to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.3.1.

Note 1

In software, programmatic determinability is best achieved through the use of accessibility services provided by platform software to enable interoperability between software and assistive technologies and accessibility features of software.

Note 2

1.3.2 Meaningful Sequence

When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined.

Applying SC 1.3.2 Meaningful Sequence to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.3.2.

1.3.3 Sensory Characteristics

Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, color, size, visual location, orientation, or sound.

Note

For requirements related to color, refer to Guideline 1.4.

Applying SC Sensory Characteristics 1.3.3 to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.3.3.

1.3.4 Orientation

Content does not restrict its view and operation to a single display orientation, such as portrait or landscape, unless a specific display orientation is essential.

Note

Examples where a particular display orientation may be essential are a bank check, a piano application, slides for a projector or television, or virtual reality content where content is not necessarily restricted to landscape or portrait display orientation.

Applying SC 1.3.4 Orientation to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.3.4.

Note 1

Content that is only used on hardware with a fixed display orientation or that has no sensor to detect or change the orientation is covered under the essential exception and does not need to provide support for orientation changes.

1.3.5 Identify Input Purpose

The purpose of each input field collecting information about the user can be programmatically determined when:

Applying SC 1.3.5 Identify Input Purpose to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.3.5.

Note 1

Non-web software and non-web documents technologies that do not provide attributes that support identifying the expected meaning for the form input data are not in scope for this success criterion.

Note 2

For non-web software and non-web documents that present input fields, the terms for the input purposes would be the equivalent terms to those listed in the WCAG 2 section Input Purposes for User Interface Components that are supported by the technology used.

Note 3

1.4 Distinguishable

Make it easier for users to see and hear content including separating foreground from background.

Applying Guideline 1.4 Distinguishable to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 1.4 applies directly as written.

1.4.1 Use of Color

Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.

Note

This success criterion addresses color perception specifically. Other forms of perception are covered in Guideline 1.3 including programmatic access to color and other visual presentation coding.

Applying SC 1.4.1 Use of Color to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.1.

1.4.2 Audio Control

If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level.

Note

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Applying SC 1.4.2 Audio Control to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.2, replacing “on a Web page” with “in a non-web document or software”, “any content” with “any part of a non-web document or software”, “whole page” with “whole document or software”, “on the Web page” with “in the document or software”, and removing “See Conformance Requirement 5: Non-Interference”.

With these substitutions, it would read:

1.4.2 Audio Control: If any audio [in a non-web document or software] plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level. (Level A)

Note 1

Since any [part of a non-web document or software] that does not meet this success criterion can interfere with a user's ability to use the [whole document or software], all content [in the document or software] (whether or not it is used to meet other success criteria) must meet this success criterion.

1.4.3 Contrast (Minimum)

The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following:

Large Text

Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;

Incidental

Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.

Logotypes

Text that is part of a logo or brand name has no contrast requirement.

Applying SC 1.4.3 Contrast Minimum to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.3.

1.4.4 Resize Text

Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality.

Applying SC 1.4.4 Resize Text to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.4.

Note 1

The Intent section refers to the ability to allow users to enlarge the text on screen at least up to 200% without needing to use assistive technologies. This means that the application provides some means for enlarging the text 200% (zoom or otherwise) without loss of content or functionality, or that the application works with the platform accessibility features to meet this success criterion.

Note 2

For non-web software, there may be cases where the platform does not scale all text up to 200%. In such cases, authors are encouraged to meet user needs by scaling text to the extent supported by user settings in the platform.

1.4.5 Images of Text

If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following:

Customizable

The image of text can be visually customized to the user's requirements;

Essential

A particular presentation of text is essential to the information being conveyed.

Note

Logotypes (text that is part of a logo or brand name) are considered essential.

Applying SC 1.4.5 Images of Text to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.5.

1.4.10 Reflow

Content can be presented without loss of information or functionality, and without requiring scrolling in two dimensions for:

  • Vertical scrolling content at a width equivalent to 320 CSS pixels;
  • Horizontal scrolling content at a height equivalent to 256 CSS pixels.

Except for parts of the content which require two-dimensional layout for usage or meaning.

Note 1

320 CSS pixels is equivalent to a starting viewport width of 1280 CSS pixels wide at 400% zoom. For web content which is designed to scroll horizontally (e.g., with vertical text), 256 CSS pixels is equivalent to a starting viewport height of 1024 CSS pixels at 400% zoom.

Note 2

Examples of content which requires two-dimensional layout are images required for understanding (such as maps and diagrams), video, games, presentations, data tables (not individual cells), and interfaces where it is necessary to keep toolbars in view while manipulating content. It is acceptable to provide two-dimensional scrolling for such parts of the content.

Applying SC 1.4.10 Reflow to Non-Web Documents and Software
Editor's note
The WCAG2ICT Task Force made changes to give additional guidance around how 1.4.10 Reflow should be applied to non-web software in response to public comments.

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.10, replacing “web content” with “content”.

With these substitutions, it would read:

Content can be presented without loss of information or functionality, and without requiring scrolling in two dimensions for:

  • Vertical scrolling content at a width equivalent to 320 CSS pixels;
  • Horizontal scrolling content at a height equivalent to 256 CSS pixels.

Except for parts of the content which require two-dimensional layout for usage or meaning.

Note 1

320 CSS pixels is equivalent to a starting viewport width of 1280 CSS pixels wide at 400% zoom. For [content] which is designed to scroll horizontally (e.g., with vertical text), 256 CSS pixels is equivalent to a starting viewport height of 1024 CSS pixels at 400% zoom.

Note 2

Examples of content which relies upon two-dimensional layout are some informative images (such as maps and diagrams), video, games, presentations, data tables (not individual cells), and interfaces where it is necessary to keep toolbars in view while manipulating content. It is acceptable to provide two-dimensional scrolling for such content.

Note 3

In technologies where CSS is not used, the definition of 'CSS pixel' applies as described in Applying “CSS pixel” to Non-Web Documents and Software.

(non-web documents)

Note 4

If a non-web document type and its available user agents do not support reflow, it may not be possible for a document of that type to meet this success criterion.

(non-web software)

Note 5

The intent section refers to the ability for content to reflow when user agent zooming is used to scale content or when the viewport changes in width. For non-web software, this means that when users scale content, adjust the size of a window or dialog, or change the screen resolution, the content will reflow without loss of information or functionality, and without requiring scrolling in two dimensions; or that the application works with platform features to meet this success criterion.

Note 6

Non-web software will have more frequent cases where two-dimensional layout is relied upon for usage or meaning than what occurs on the Web. For example:

  • When the software has a complex user interface with toolbars that need to be visible while manipulating content, as explained in the Intent from Understanding 1.4.10 Reflow.
Note 7

As written, this success criterion can only be met by non-web documents or software where the underlying user agent or platform can present content at a width equivalent to 320 CSS pixels for vertical scrolling content and a height equivalent to 256 CSS pixels for horizontal scrolling content.

When the underlying user agent or platform does not support these dimensions for scrolling, reflow is encouraged as this capability is important to persons with low vision. As a reasonable benchmark, evaluate at the nearest size to what the Reflow success criterion specifies.

Note 8

Some software applications provide a mode of operation where reflow is possible, while other modes are unable to reflow. An example is a document authoring tool, which includes both a "print preview mode" (without reflow, for users to view the spatial formatting) and a "drafting view mode" where reflow is supported.

1.4.11 Non-text Contrast

The visual presentation of the following have a contrast ratio of at least 3:1 against adjacent color(s):

User Interface Components
Visual information required to identify user interface components and states, except for inactive components or where the appearance of the component is determined by the user agent and not modified by the author;
Graphical Objects
Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.
Applying SC 1.4.11 Non-text Contrast to Non-Web Documents and Software

This applies directly as written and as described in Intent from Understanding Success Criterion 1.4.11, replacing "user agent" with "user agent or platform software".

With these substitutions, it would read:

The visual presentation of the following have a contrast ratio of at least 3:1 against adjacent color(s):

  • User Interface Components: Visual information required to identify user interface components and states, except for inactive components or where the appearance of the component is determined by the [user agent or platform software] and not modified by the author;

  • Graphical Objects: Parts of graphics required to understand the content, except when a particular presentation of graphics is essential to the information being conveyed.

Note 1

An example of appearance modification by the author is content that sets the visual style of a control, such as a color or border, to differ from the default style for the user agent or platform.

1.4.12 Text Spacing

In content implemented using markup languages that support the following text style properties, no loss of content or functionality occurs by setting all of the following and by changing no other style property:

  • Line height (line spacing) to at least 1.5 times the font size;
  • Spacing following paragraphs to at least 2 times the font size;
  • Letter spacing (tracking) to at least 0.12 times the font size;
  • Word spacing to at least 0.16 times the font size.

Exception: Human languages and scripts that do not make use of one or more of these text style properties in written text can conform using only the properties that exist for that combination of language and script.

Note 1

Content is not required to use these text spacing values. The requirement is to ensure that when a user overrides the authored text spacing, content or functionality is not lost.

Note 2

Writing systems for some languages use different text spacing settings, such as paragraph start indent. Authors are encouraged to follow locally available guidance for improving readability and legibility of text in their writing system.

Applying SC 1.4.12 Text Spacing to Non-Web Documents and Software

This applies directly as written and as described in Intent from Understanding Success Criterion 1.4.12.

Note 1

This success criterion only applies to non-web documents and software that are implemented using markup languages and allow the user to modify these text spacing properties.

Note 2

"Content implemented using markup languages" includes parts of software that use markup internally to define a user interface. Examples of markup languages that are used internally to define a software user interface include but are not limited to: HTML (e.g., in Electron applications or iOS application Web views), XAML, XML (e.g., in Android application layouts), and XUL.

Note 3

There are several mechanisms that allow users to modify text spacing properties of content implemented in markup languages. For example, an eBook technology may have an available user agent that allows users to override document text styles, or a software application may provide a "user style sheet" facility to modify the appearance of the software's own user interface. This success criterion does not mean that documents and software need to implement their own mechanisms to allow users to set text spacing; however, when such a mechanism is available, the success criterion requires that content respond appropriately to it.

1.4.13 Content on Hover or Focus

Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:

Dismissible
A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;
Hoverable
If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;
Persistent
The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.

Exception: The visual presentation of the additional content is controlled by the user agent and is not modified by the author.

Note 1

Examples of additional content controlled by the user agent include browser tooltips created through use of the HTML title attribute [HTML].

Note 2

Custom tooltips, sub-menus, and other nonmodal popups that display on hover and focus are examples of additional content covered by this criterion.

Note 3

This criterion applies to content that appears in addition to the triggering component itself. Since hidden components that are made visible on keyboard focus (such as links used to skip to another part of a page) do not present additional content they are not covered by this criterion.

Applying SC 1.4.13 Content on Hover or Focus to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 1.4.13, replacing "user agent" with "user agent or platform software", "browser tooltips" with "tooltips", and "the HTML title attribute" with "user interface object attributes".

With these substitutions, it would read:

Where receiving and then removing pointer hover or keyboard focus triggers additional content to become visible and then hidden, the following are true:

Dismissible A mechanism is available to dismiss the additional content without moving pointer hover or keyboard focus, unless the additional content communicates an input error or does not obscure or replace other content;

Hoverable If pointer hover can trigger the additional content, then the pointer can be moved over the additional content without the additional content disappearing;

Persistent The additional content remains visible until the hover or focus trigger is removed, the user dismisses it, or its information is no longer valid.

Exception: The visual presentation of the additional content is controlled by the [user agent or platform software] and is not modified by the author.

Note 1

Examples of additional content controlled by the [user agent or platform software] include [tooltips] created through use of [user interface object attributes].

Note 2
Custom tooltips, sub-menus, and other nonmodal popups that display on hover and focus are examples of additional content covered by this criterion.
Note 3

This criterion applies to content that appears in addition to the triggering component itself. Since hidden components that are made visible on keyboard focus (such as links used to skip to another part of a page) do not present additional content they are not covered by this criterion.

2. Operable

User interface components and navigation must be operable.

Applying Principle 2 Operable to Non-Web Documents and Software

In WCAG 2, the Principles are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Principle 2 applies directly as written.

2.1 Keyboard Accessible

Make all functionality available from a keyboard.

Applying Guideline 2.1 Keyboard Accessible to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 2.1 applies directly as written.

2.1.1 Keyboard

All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints.

Note 1

This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path-dependent input but the underlying function (text input) does not.

Note 2

This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.

Applying SC 2.1.1 Keyboard to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.1.1.

Note 1

This does not imply that software always needs to directly support a keyboard or “keyboard interface”. Nor does it imply that software always needs to provide a soft keyboard. Underlying platform software may provide device independent input services to applications that enable operation via a keyboard. Software that supports operation via such platform device independent services would be operable by a keyboard and would comply.

2.1.2 No Keyboard Trap

If keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away.

Note

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Applying SC 2.1.2 No Keyboard Trap to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.1.2, replacing “page” with “non-web document or software”, and “on the Web page” with "in the non-web document or software", and removing “See Conformance Requirement 5: Non-Interference”.

With these substitutions, it would read:

2.1.2 No Keyboard Trap: If keyboard focus can be moved to a component of the [non-web document or software] using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away. (Level A)

Note 1

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole [non-web document or software], all content [in the non-web document or software] (whether it is used to meet other success criteria or not) must meet this success criterion.

Note 2

Standard exit methods may vary by platform. For example, on many desktop platforms, the Escape key is a standard method for exiting.

Note 3

This criterion applies when focus can be moved using a keyboard interface. Some software may accept input from a keyboard, keypad, or controller, yet not offer any mechanism for focus; for example, the keys are mapped directly to functions without moving focus between on-screen controls. In this case, there is no concept of focus, and therefore keyboard traps cannot exist and this success criterion would be satisfied.

2.1.4 Character Key Shortcuts

If a keyboard shortcut is implemented in content using only letter (including upper- and lower-case letters), punctuation, number, or symbol characters, then at least one of the following is true:

Turn off
A mechanism is available to turn the shortcut off;
Remap
A mechanism is available to remap the shortcut to include one or more non-printable keyboard keys (e.g., Ctrl, Alt);
Active only on focus
The keyboard shortcut for a user interface component is only active when that component has focus.
Applying SC 2.1.4 Character Key Shortcuts to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.1.4.

Note 1

The WCAG2ICT interpretation is that a long press of a key (2 seconds or more) and other accessibility features provided by the platform do not meet the WCAG definition of a keyboard shortcut. See the keyboard shortcut definition for more details.

2.2 Enough Time

Provide users enough time to read and use content.

Applying Guideline 2.2 Enough Time to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not used for conformance to WCAG. Guideline 2.2 applies directly as written.

2.2.1 Timing Adjustable

For each time limit that is set by the content, at least one of the following is true:

Turn off

The user is allowed to turn off the time limit before encountering it; or

Adjust

The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or

Extend

The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times; or

Real-time Exception

The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or

Essential Exception

The time limit is essential and extending it would invalidate the activity; or

20 Hour Exception

The time limit is longer than 20 hours.

Note

This success criterion helps ensure that users can complete tasks without unexpected changes in content or context that are a result of a time limit. This success criterion should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.

Applying SC 2.2.1 Timing Adjustable to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.2.1, replacing “the content” with “non-web documents or software”.

With this substitution, it would read:

2.2.1 Timing Adjustable: For each time limit that is set by [non-web documents or software], at least one of the following is true: (Level A)

  • Turn off: The user is allowed to turn off the time limit before encountering it; or
  • Adjust: The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or
  • Extend: The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, “press the space bar”), and the user is allowed to extend the time limit at least ten times; or
  • Real-time Exception: The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or
  • Essential Exception: The time limit is essential and extending it would invalidate the activity; or
  • 20 Hour Exception: The time limit is longer than 20 hours.
Note

This success criterion helps ensure that users can complete tasks without unexpected changes in content or context that are a result of a time limit. This success criterion should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.

2.2.2 Pause, Stop, Hide

For moving, blinking, scrolling, or auto-updating information, all of the following are true:

Moving, blinking, scrolling

For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and

Auto-updating

For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.

Note 1

For requirements related to flickering or flashing content, refer to Guideline 2.3.

Note 2

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Note 3

Content that is updated periodically by software or that is streamed to the user agent is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.

Note 4

An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users and if not indicating progress could confuse users or cause them to think that content was frozen or broken.

Applying SC 2.2.2 Pause, Stop, Hide to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.2.2, replacing “page” and “Web page” with “non-web documents and software” and removing “See Conformance Requirement 5: Non-Interference” in Note 2 of the success criterion.

With this substitution, it would read:

2.2.2 Pause, Stop, Hide: For moving, blinking, scrolling, or auto-updating information, all of the following are true: (Level A)

  • Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and

  • Auto-updating: For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.

Note 1

For requirements related to flickering or flashing content, refer to Guideline 2.3.

Note 2

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole [non-web documents and software], all content on the [non-web documents and software] (whether it is used to meet other success criteria or not) must meet this success criterion.

Note 3

Content that is updated periodically by software or that is streamed to the user agent is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.

Note 4

An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users and if not indicating progress could confuse users or cause them to think that content was frozen or broken.

Note 5

While the success criteria uses the term “information”, the WCAG 2 Intent section makes it clear that this is to be applied to all content. Any content, whether informative or decorative, that is updated automatically, blinks, or moves may create an accessibility barrier.

2.3 Seizures and Physical Reactions

Do not design content in a way that is known to cause seizures or physical reactions.

Applying Guideline 2.3 Seizures and Physical Reactions to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 2.3 applies directly as written.

2.3.1 Three Flashes or Below Threshold

Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds.

Note

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Applying SC 2.3.1 Three Flashes or Below Threshold to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.3.1, replacing “Web pages” with “non-web documents or software” , “the whole page” with “the whole non-web document or software”, “the Web page” with “the non-web document or software”, and removing “See Conformance Requirement 5: Non-Interference”.

With these substitutions, it would read:

2.3.1 Three Flashes or Below Threshold: [Non-web documents or software] do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds. (Level A)

Note

Since any content that does not meet this success criterion can interfere with a user's ability to use the whole [non-web document or software], all content on the [non-web document or software] (whether it is used to meet other success criteria or not) must meet this success criterion.

2.5 Input Modalities

Make it easier for users to operate functionality through various inputs beyond keyboard.

Applying Guideline 2.5 Input Modalities to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 2.5 applies directly as written.

2.5.1 Pointer Gestures

All functionality that uses multipoint or path-based gestures for operation can be operated with a single pointer without a path-based gesture, unless a multipoint or path-based gesture is essential.

Note

This requirement applies to web content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Applying SC 2.5.1 Pointer Gestures to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.1, making changes to the notes for non-web documents by replacing “web content” with "content", for non-web software applications by replacing "web content that interprets" with "user agents and other software applications that interpret" and "user agent" with "underlying platform software", and for non-web platform software replacing "web content" with "platform software".

With these substitutions, the notes would read:

(non-web documents)

Note 1

This requirement applies to [content] that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Note 2

Multipoint and path-based gestures are less common in documents. An example where a document author could add such gestures is an interactive prototype document created in a software design tool.

(non-web software)

Note 3

This requirement applies to [user agents and other software applications that interpret] pointer actions (i.e. this does not apply to actions that are required to operate the [underlying platform software] or assistive technology).

Note 4

This requirement also applies to [platform software] that interprets pointer actions (i.e. this does not apply to actions that are required to operate the assistive technology).

2.5.2 Pointer Cancellation

For functionality that can be operated using a single pointer, at least one of the following is true:

No Down-Event
The down-event of the pointer is not used to execute any part of the function;
Abort or Undo
Completion of the function is on the up-event, and a mechanism is available to abort the function before completion or to undo the function after completion;
Up Reversal
The up-event reverses any outcome of the preceding down-event;
Essential
Completing the function on the down-event is essential.
Note 1

Functions that emulate a keyboard or numeric keypad key press are considered essential.

Note 2

This requirement applies to web content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Applying SC 2.5.2 Pointer Cancellation to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.2, making changes to the notes for non-web documents by replacing “web content” with "content", for non-web software applications by replacing "web content that interprets" with "user agents and other software applications that interpret" and "user agent" with "underlying platform software", and for non-web platform software replacing "web content" with "platform software".

With these substitutions, the notes would read:

(for non-web documents)

Note 1

Functions that emulate a keyboard or numeric keypad key press are considered essential.

Note 2

This requirement applies to [content] that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Note 3

Content that interprets pointer actions and controls which events are used for executing functionality is less common in documents. An example where a document author could add such functionality is an interactive prototype document created in a software design tool.

(for non-web software)

Note 4

Functions that emulate a keyboard or numeric keypad key press are considered essential. [Examples of essential functionality for non-web software are features for meeting environmental energy usage requirements (like waking a device from sleep, power saver mode, and low power state).]

Note 5

This requirement applies to [user agents and other software applications that interpret] pointer actions (i.e. this does not apply to actions that are required to operate the [underlying platform software] or assistive technology).

Note 6

This requirement also applies to [platform software] that interprets pointer actions (i.e. this does not apply to actions that are required to operate the assistive technology).

2.5.3 Label in Name

For user interface components with labels that include text or images of text, the name contains the text that is presented visually.

Note

A best practice is to have the text of the label at the start of the name.

Applying SC 2.5.3 Label in Name to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.3.

2.5.4 Motion Actuation

Functionality that can be operated by device motion or user motion can also be operated by user interface components and responding to the motion can be disabled to prevent accidental actuation, except when:

Supported Interface
The motion is used to operate functionality through an accessibility supported interface;
Essential
The motion is essential for the function and doing so would invalidate the activity.
Applying SC 2.5.4 Motion Actuation to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.4.

2.5.7 Dragging Movements

[New]

All functionality that uses a dragging movement for operation can be achieved by a single pointer without dragging, unless dragging is essential or the functionality is determined by the user agent and not modified by the author.

Note

This requirement applies to web content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Applying SC 2.5.7 Dragging Movements to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.7, replacing "user agent" with "user agent or platform software", and making changes to the notes for non-web documents by replacing “web content” with "content", for non-web software applications by replacing "web content that interprets" with "user agents and other software applications that interpret" and "user agent" with "underlying platform software", and for non-web platform software replacing "web content" with "platform software".

With these substitutions, it would read:

All functionality that uses a dragging movement for operation can be achieved by a single pointer without dragging, unless dragging is essential or the functionality is determined by the [user agent or platform software] and not modified by the author.

(non-web documents)

Note 1

This requirement applies to content that interprets pointer actions (i.e. this does not apply to actions that are required to operate the user agent or assistive technology).

Note 2

Dragging movements for operation are less common in documents. An example where a document author could add dragging functionality is an interactive prototype document created in a software design tool.

(non-web software)

Note 3

This requirement applies to [user agents and other software applications that interpret] pointer actions (i.e. this does not apply to actions that are required to operate the [underlying platform software] or assistive technology).

Note 4

This requirement also applies to [platform software] that interprets pointer actions (i.e. this does not apply to actions that are required to operate the assistive technology).

2.5.8 Target Size (Minimum)

[New]

The size of the target for pointer inputs is at least 24 by 24 CSS pixels, except where:

  • Spacing: Undersized targets (those less than 24 by 24 CSS pixels) are positioned so that if a 24 CSS pixel diameter circle is centered on the bounding box of each, the circles do not intersect another target or the circle for another undersized target;
  • Equivalent: The function can be achieved through a different control on the same page that meets this criterion;
  • Inline: The target is in a sentence or its size is otherwise constrained by the line-height of non-target text;
  • User agent control: The size of the target is determined by the user agent and is not modified by the author;
  • Essential: A particular presentation of the target is essential or is legally required for the information being conveyed.
Note 1

Targets that allow for values to be selected spatially based on position within the target are considered one target for the purpose of the success criterion. Examples include sliders, color pickers displaying a gradient of colors, or editable areas where you position the cursor.

Note 2

For inline targets the line-height should be interpreted as perpendicular to the flow of text. For example, in a language displayed vertically, the line-height would be horizontal.

Applying SC 2.5.8 Target Size (Minimum) to Non-Web Documents and Software:

This applies directly as written, and as described in Intent from Understanding Success Criterion 2.5.8, replacing "user agent" with "user agent or platform software", and "on the same page" with "in the same non-web document or software".

With these substitutions, it would read:

The size of the target for pointer inputs is at least 24 by 24 CSS pixels, except where:

  • Spacing: Undersized targets (those less than 24 by 24 CSS pixels) are positioned so that if a 24 CSS pixel diameter circle is centered on the bounding box of each, the circles do not intersect another target or the circle for another undersized target;
  • Equivalent: The function can be achieved through a different control [in the same non-web document or software] that meets this criterion.
  • Inline: The target is in a sentence or its size is otherwise constrained by the line-height of non-target text;
  • [User agent or platform software] control: The size of the target and target offset is determined by the [user agent or platform software] and is not modified by the author;
  • Essential: A particular presentation of the target is essential or is legally required for the information being conveyed;
Note 1

Targets that allow for values to be selected spatially based on position within the target are considered one target for the purpose of the success criterion. Examples include sliders with granular values, color pickers displaying a gradient of colors, or editable areas where you position the cursor.

Note 2

For inline targets the line-height should be interpreted as perpendicular to the flow of text. For example, in a language displayed vertically, the line-height would be horizontal.

Note 3

In technologies where CSS is not used, the definition of 'CSS pixel' applies as described in Applying “CSS pixel” to Non-Web Documents and Software.

(for non-web documents)

Note 4

Some document formats are designed for viewing at a wide range of zoom levels provided by the user agent. However, the commonly available user agents for these formats may lack a consistent base zoom level from which to evaluate this criterion. For such documents, evaluate target sizes at a zoom level that aligns with the intended usage of the content.

(for non-web software)

3. Understandable

Information and the operation of the user interface must be understandable.

Applying Principle 3 Understandable to Non-Web Documents and Software

In WCAG 2, the Principles are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Principle 3 applies directly as written.

3.1 Readable

Make text content readable and understandable.

Applying Guideline 3.1 Readable to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 3.1 applies directly as written.

3.1.1 Language of Page

The default human language of each Web page can be programmatically determined.

Applying SC 3.1.1 Language of Page to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.1.1 replacing “each web page” with non-web documents or software.

With these substitutions, it would read:

3.1.1 Language of Page: The default human language of [non-web documents or software] can be programmatically determined. (Level A)

Note 1

Where software platforms provide a “locale / language” setting, applications that use that setting and render their interface in that “locale / language” would comply with this success criterion. Applications that do not use the platform “locale / language” setting but instead use an accessibility-supported method for exposing the human language of the software would also comply with this success criterion. Applications implemented in technologies where assistive technologies cannot determine the human language and that do not support the platform “locale / language” setting may not be able to meet this success criterion in that locale / language.

3.1.2 Language of Parts

The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text.

Applying SC 3.1.2 Language of Parts to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.1.2 replacing “content” with “non-web document or software”.

With these substitutions, it would read:

3.1.2 Language of Parts: The human language of each passage or phrase in the [non-web document or software] can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text. (Level AA)

Note 1

There are some software and non-web document technologies where there is no assistive technology supported method for marking the language for the different passages or phrases in the non-web document or software, and it would not be possible to meet this success criterion with those technologies.

3.2 Predictable

Make Web pages appear and operate in predictable ways.

Applying Guideline 3.2 Predictable to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 3.2 applies directly as written, replacing “web pages” with “non-web documents or software”.

With this substitution, this guideline would read:

Guideline 3.2 Predictable: Make [non-web documents or software] appear and operate in predictable ways.

3.2.1 On Focus

When any user interface component receives focus, it does not initiate a change of context.

Applying SC 3.2.1 On Focus to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.2.1.

Note

Some compound documents and their user agents are designed to provide significantly different viewing and editing functionality depending upon what portion of the compound document is being interacted with (e.g. a presentation that contains an embedded spreadsheet, where the menus and toolbars of the user agent change depending upon whether the user is interacting with the presentation content, or the embedded spreadsheet content). If the user uses a mechanism other than putting focus on that portion of the compound document with which they mean to interact (e.g. by a menu choice or special keyboard gesture), any resulting change of context wouldn't be subject to this success criterion because it was not caused by a change of focus.

3.2.2 On Input

Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component.

Applying SC 3.2.2 On Input to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.2.2.

3.2.3 Consistent Navigation

Navigational mechanisms that are repeated on multiple Web pages within a set of Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user.

Applying SC 3.2.3 Consistent Navigation to Non-Web Documents and Software

This applies directly as written and described in Intent from Understanding Success Criterion 3.2.3, replacing “set of Web pages” with “set of non-web documents” and “set of software programs”.

With these substitutions, this success criterion would read:

(for non-web documents)

3.2.3 Consistent Navigation: Navigational mechanisms that are repeated on multiple [non-web documents] within a [set of non-web documents] occur in the same relative order each time they are repeated, unless a change is initiated by the user.

(for software programs)

3.2.3 Consistent Navigation: Navigational mechanisms that are repeated on multiple [software programs] within a [set of software programs] occur in the same relative order each time they are repeated, unless a change is initiated by the user.

Note 1

See set of documents and set of software programs in the Key Terms section of the Introduction to determine when a group of documents or software programs is considered a set for this success criterion. (Sets of software that meet this definition appear to be extremely rare.) Those implementing this document (WCAG2ICT) will need to consider if this success criterion is appropriate to apply to non-web documents and software. See the Interpretation of Web Terminology in a Non-web Context.

Note 2

Although not required by this success criterion, ensuring that navigation elements have consistent order when repeated within non-web documents or software programs directly addresses user needs identified in the Intent section for this success criterion, and is generally considered best practice.

3.2.4 Consistent Identification

Components that have the same functionality within a set of Web pages are identified consistently.

Applying SC 3.2.4 Consistent Identification to Non-Web Documents and Software

This applies directly as written and described in Intent from Understanding Success Criterion 3.2.4, replacing “set of web pages” with “set of non-web documents” and “set of software programs”.

With these substitutions, this success criterion would read:

(for non-web documents)

3.2.4 Consistent Identification: Components that have the same functionality within a [set of non-web documents] are identified consistently.

(for programs)

3.2.4 Consistent Identification: Components that have the same functionality within a [set of software programs] are identified consistently.

Note 1

See set of documents and set of software programs in the Key Terms section of the Introduction to determine when a group of documents or software programs is considered a set for this success criterion. (Sets of software that meet this definition appear to be extremely rare.) Those implementing this document (WCAG2ICT) will need to consider if this success criterion is appropriate to apply to non-web documents and software. See the Interpretation of Web Terminology in a Non-web Context.

Note 2

Although not required by this success criterion, ensuring that component identification be consistent when they occur more than once within non-web documents or software programs directly addresses user needs identified in the Intent section for this success criterion, and is generally considered best practice.

3.2.6 Consistent Help

[New]

If a Web page contains any of the following help mechanisms, and those mechanisms are repeated on multiple Web pages within a set of Web pages, they occur in the same order relative to other page content, unless a change is initiated by the user:

  • Human contact details;
  • Human contact mechanism;
  • Self-help option;
  • A fully automated contact mechanism.
Note 1

Help mechanisms may be provided directly on the page, or may be provided via a direct link to a different page containing the information.

Note 2

For this Success Criterion, "the same order relative to other page content" can be thought of as how the content is ordered when the page is serialized. The visual position of a help mechanism is likely to be consistent across pages for the same page variation (e.g., CSS break-point). The user can initiate a change, such as changing the page's zoom or orientation, which may trigger a different page variation. This criterion is concerned with relative order across pages displayed in the same page variation (e.g., same zoom level and orientation).

Applying SC 3.2.6 Consistent Help to Non-Web Documents and Software

This applies directly as written and as described in Intent from Understanding Success Criterion 3.2.6, replacing "Web page(s)" and "page(s)" with "non-web document(s) or software program(s)", "set of Web pages" with "set of non-web documents or set of software programs", "page content" with "content", "on the page" with "in the non-web document or software", "page is serialized" with "non-web document or software content is serialized", "different page" with "different non-web document, software, or Web page", and "page variation" with "content layout variation".

With these substitutions, this success criterion would read:

If a [non-web document or software] contains any of the following help mechanisms, and those mechanisms are repeated [in multiple non-web documents or software] within a [set of non-web documents or set of software programs], they occur in the same order relative to other [content], unless a change is initiated by the user:

  • Human contact details;
  • Human contact mechanism;
  • Self-help option;
  • A fully automated contact mechanism
Note 1

Help mechanisms may be provided directly [in the non-web document or software], or may be provided via a direct link to a [different non-web document, software, or Web page] containing the information.

Note 2

For this success criterion, "the same order relative to other [content]" can be thought of as how the content is ordered when the [non-web document or software content is serialized]. The visual position of a help mechanism is likely to be consistent across [non-web documents or software] for the same [content layout variation] (e.g., CSS break-point). The user can initiate a change, such as changing the [non-web document’s or software's] zoom or orientation, which may trigger a different [content layout variation]. This criterion is concerned with relative order across [non-web documents or software] displayed in the same [content layout variation] (e.g., same zoom level and orientation).

Note 3

See set of documents and set of software programs in the Key Terms section of the Introduction to determine when a group of documents or pieces of software is considered a set for this success criterion. (Sets of software that meet this definition appear to be extremely rare.) Those implementing this document (WCAG2ICT) will need to consider if this success criterion is appropriate to apply to non-web documents and software. See the Interpretation of Web Terminology in a Non-web Context.

3.3 Input Assistance

Help users avoid and correct mistakes.

Applying Guideline 3.3 Input Assistance to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 3.3 applies directly as written.

3.3.1 Error Identification

If an input error is automatically detected, the item that is in error is identified and the error is described to the user in text.

Applying SC 3.3.1 Error Identification to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.3.1.

3.3.2 Labels or Instructions

Labels or instructions are provided when content requires user input.

Applying SC 3.3.2 Labels or Instructions to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.3.2.

3.3.3 Error Suggestion

If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content.

Applying SC 3.3.3 Error Suggestion to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.3.3.

3.3.7 Redundant Entry

[New]

Information previously entered by or provided to the user that is required to be entered again in the same process is either:

  • auto-populated, or
  • available for the user to select.

Except when:

  • re-entering the information is essential,
  • the information is required to ensure the security of the content, or
  • previously entered information is no longer valid.
Applying SC 3.3.7 Redundant Entry to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.3.7.

3.3.8 Accessible Authentication (Minimum)

[New]

A cognitive function test (such as remembering a password or solving a puzzle) is not required for any step in an authentication process unless that step provides at least one of the following:

Alternative
Another authentication method that does not rely on a cognitive function test.
Mechanism
A mechanism is available to assist the user in completing the cognitive function test.
Object Recognition
The cognitive function test is to recognize objects.
Personal Content
The cognitive function test is to identify non-text content the user provided to the Web site.
Note 1

"Object recognition" and "Personal content" may be represented by images, video, or audio.

Note 2
Examples of mechanisms that satisfy this criterion include:
  1. support for password entry by password managers to reduce memory need, and
  2. copy and paste to reduce the cognitive burden of re-typing.
Applying SC 3.3.8 Accessible Authentication (Minimum) to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 3.3.8, “the Web site” with “a Web site, non-web document, or software”.

A cognitive function test (such as remembering a password or solving a puzzle) is not required for any step in an authentication process unless that step provides at least one of the following:

Alternative
Another authentication method that does not rely on a cognitive function test.
Mechanism
A mechanism is available to assist the user in completing the cognitive function test.
Object Recognition
The cognitive function test is to recognize objects.
Personal Content
The cognitive function test is to identify non-text content the user provided to a Web site, non-web document, or software.
Note 1

"Object recognition" and "Personal content" may be represented by images, video, or audio.

Note 2

Examples of mechanisms that satisfy this criterion include: support for password entry by password managers to reduce memory need, and copy and paste to reduce the cognitive burden of re-typing.

Note 3

If the non-web software is an application, passwords used to unlock the underlying platform software are out of scope for this requirement as these are not up to a software application’s author.

4. Robust

Content must be robust enough that it can be interpreted by a wide variety of user agents, including assistive technologies.

Applying Principle 4 Robust to Non-Web Documents and Software

In WCAG 2, the Principles are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Principle 4 applies directly as written replacing “user agents, including assistive technologies” with “assistive technologies and accessibility features of software”.

With this substitution, it would read:

Principle 4: Robust - Content must be robust enough that it can be interpreted reliably by a wide variety of [assistive technologies and accessibility features of software].

4.1 Compatible

Maximize compatibility with current and future user agents, including assistive technologies.

Applying Guideline 4.1 Compatible to Non-Web Documents and Software

In WCAG 2, the Guidelines are provided for framing and understanding the success criteria under them but are not required for conformance to WCAG. Guideline 4.1 applies directly as written, replacing “user agents, including assistive technologies” with “assistive technologies and accessibility features of software”.

With this substitution, it would read:

Guideline 4.1 Compatible: Maximize compatibility with current and future [assistive technologies and accessibility features of software].

4.1.1 Parsing (Obsolete and removed)
Note

This criterion was originally adopted to address problems that assistive technology had directly parsing HTML. Assistive technology no longer has any need to directly parse HTML. Consequently, these problems either no longer exist or are addressed by other criteria. This criterion no longer has utility and is removed.

Applying SC 4.1.1 Parsing to Non-Web Documents and Software
Editor's note

This section has been updated to reflect that WCAG 2.2 made 4.1.1 obsolete and removed. For WCAG 2.0 and 2.1, the 2013 WCAG2ICT guidance has been updated to reflect more current technology examples, the WCAG errata regarding content implemented using HTML and XML, and to address comments received.

WCAG 2.2 Guidance:

Note 1

WCAG 2.2 has made this success criterion obsolete and removed it as a requirement in the standard. Therefore, the interpretation of this success criterion for non-web documents and software has been removed.

WCAG 2.0 and 2.1 Guidance:

This applies directly as written, and as described in Intent from Understanding Success Criterion 4.1.1, replacing “In content implemented using markup languages” with “For non-web documents or software that use markup languages, in such a way that the markup is separately exposed and available to assistive technologies and accessibility features of software or to a user-selectable user agent”. With these substitutions, it would read:

4.1.1 Parsing: [For non-web documents or software that use markup languages, in such a way that the markup is separately exposed and available to assistive technologies and accessibility features of software or to a user-selectable user agent], elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features.

Note 2

Start and end tags that are missing a critical character in their formation, such as a closing angle bracket or a mismatched attribute value quotation mark are not complete.

Note 3

Markup is not always available to assistive technologies or to user selectable user agents such as browsers. Software sometimes uses markup languages internally for persistence of the software user interface, in ways where the markup is never available to assistive technology (either directly or through a document object model (DOM)), or to a user agent (such as a browser). In such cases, conformance to this provision would have no impact on accessibility as it can have for web content where it is exposed.

Accessibility issues introduced through poor markup would surface as errors in the programmatic information and would be reported using success criteria that rely on that information, such as 1.3.1 Info and Relationships and 4.1.2 Name, Role, Value.

Note 4

This success criterion would be satisfied in cases where:

  • Content is implemented using HTML or XML (per the WCAG errata.)
  • Non-web documents or software are not authored using a markup language.
  • Non-web documents or software are authored using a markup language, but accessibility information is exposed via platform accessibility APIs, not by making the markup itself available to assistive technologies.

Example: Examples where 4.1.1 Parsing would be satisfied:

  • An HTML page embedded inside a desktop application (per the WCAG errata)
  • A PDF document (not authored using a markup language)
  • Android or iOS apps which use a markup language to specify UI layout (accessibility information is exposed via platform accessibility APIs, not the markup)

Examples of markup that might be separately exposed and available to assistive technologies and to user agents include:

  • LaTeX documents
  • Markdown documents
4.1.2 Name, Role, Value

For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies.

Note

This success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.

Applying SC 4.1.2 Name, Role, Value to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 4.1.2, replacing the note with: “This success criterion is primarily for software developers who develop or use custom user interface components. For example, standard user interface components on most accessibility-supported platforms already meet this success criterion when used according to specification.”.

With this substitution, it would read:

4.1.2 Name, Role, Value: For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies. (Level A)

Note 1

[This success criterion is primarily for software developers who develop or use custom user interface components. Standard user interface components on most accessibility-supported platforms already meet this success criterion when used according to specification.]

Note 2

For conforming to this success criterion, it is usually best practice for software user interfaces to use the accessibility services provided by platform software. These accessibility services enable interoperability between software user interfaces and both assistive technologies and accessibility features of software in standardized ways. Most platform accessibility services go beyond programmatic exposure of name and role, and programmatic setting of states, properties and values (and notification of same), and specify additional information that could be exposed and / or set (for instance, a list of the available actions for a given user interface component, and a means to programmatically execute one of the listed actions).

Note 3

For document formats that support interoperability with assistive technology, standard user interface components often meet this success criterion when used according to the general design and accessibility guidance for the document format.

4.1.3 Status Messages

In content implemented using markup languages, status messages can be programmatically determined through role or properties such that they can be presented to the user by assistive technologies without receiving focus.

Applying SC 4.1.3 Status Messages to Non-Web Documents and Software

This applies directly as written, and as described in Intent from Understanding Success Criterion 4.1.3.

Note 1

For non-web documents and software where status messages are not implemented using markup languages, there is still a user need to have status messages be programmatically exposed so that they can be presented to the user by assistive technologies without receiving focus. This is typically enabled through the use of accessibility services of the user agent or platform software.

Comments on Definitions in WCAG 2 Glossary

Editor's note

This draft of WCAG2ICT added guidance on applying new WCAG 2.2 glossary terms to non-web documents and software. The following terms were added since the First Public Working Draft: Cognitive function test, dragging movements, encloses, focus indicator, minimum bounding box, and perimeter. Of those terms, only perimeter needed WCAG2ICT guidance when applied to non-web documents and software. In addition, guidance for the term CSS pixel was updated to address public comments.

The following is a complete list of definitions from the WCAG 2 glossary. Some items apply to all technologies and do not require additional guidance in this document; guidance on the remainder follows.

Glossary Items that Apply to All Technologies

The following glossary items apply to all technologies and do not need further interpretation for non-web ICT.

Glossary Items Used only in AAA Success Criteria

This document does not provide guidance on applying AAA success criteria to non-web ICT, including the following definitions.

Glossary Items with Specific Guidance

Additional guidance is provided for the following glossary entries from WCAG 2 when applying them to non-web documents and software.

accessibility supported

supported by users' assistive technologies as well as the accessibility features in browsers and other user agents

To qualify as an accessibility-supported use of a Web content technology (or feature of a technology), both 1 and 2 must be satisfied for a Web content technology (or feature):

  1. The way that the Web content technology is used must be supported by users' assistive technology (AT). This means that the way that the technology is used has been tested for interoperability with users' assistive technology in the human language(s) of the content,

    AND

  2. The Web content technology must have accessibility-supported user agents that are available to users. This means that at least one of the following four statements is true:

    1. The technology is supported natively in widely-distributed user agents that are also accessibility supported (such as HTML and CSS);

      OR

    2. The technology is supported in a widely-distributed plug-in that is also accessibility supported;

      OR

    3. The content is available in a closed environment, such as a university or corporate network, where the user agent required by the technology and used by the organization is also accessibility supported;

      OR

    4. The user agent(s) that support the technology are accessibility supported and are available for download or purchase in a way that:

      • does not cost a person with a disability any more than a person without a disability and
      • is as easy to find and obtain for a person with a disability as it is for a person without disabilities.
Note 1

The Accessibility Guidelines Working Group and the W3C do not specify which or how much support by assistive technologies there must be for a particular use of a Web technology in order for it to be classified as accessibility supported. (See Level of Assistive Technology Support Needed for "Accessibility Support".)

Note 2

Web technologies can be used in ways that are not accessibility supported as long as they are not relied upon and the page as a whole meets the conformance requirements, including Conformance Requirement 4 and Conformance Requirement 5.

Note 3

When a Web Technology is used in a way that is "accessibility supported," it does not imply that the entire technology or all uses of the technology are supported. Most technologies, including HTML, lack support for at least one feature or use. Pages conform to WCAG only if the uses of the technology that are accessibility supported can be relied upon to meet WCAG requirements.

Note 4

When citing Web content technologies that have multiple versions, the version(s) supported should be specified.

Note 5

One way for authors to locate uses of a technology that are accessibility supported would be to consult compilations of uses that are documented to be accessibility supported. (See Understanding Accessibility-Supported Web Technology Uses.) Authors, companies, technology vendors, or others may document accessibility-supported ways of using Web content technologies. However, all ways of using technologies in the documentation would need to meet the definition of accessibility-supported Web content technologies above.

Applying “accessibility supported” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “browsers and other user agents” with “user agents or other software”, replacing “user agents” with “user agents or other software”, replacing “web content technology” with “non-web document or software technology”, adding “or other software extension” after “plug-in”, and replacing all five of the Notes with a single Note: “Note: The concepts behind the five Notes and in Understanding Accessibility Supported are applicable to web technologies. The same or similar factors are applicable for non-web technologies.”

With these substitutions and addition, it would read:

accessibility supported

supported by users' assistive technologies as well as the accessibility features in [user agents or other software]

To qualify as an accessibility-supported use of a [non-web document or software] technology (or feature of a technology), both 1 and 2 must be satisfied for a [non-web document or software] technology (or feature):

  1. The way that the [non-web document or software technology] is used must be supported by users' assistive technology (AT). This means that the way that the technology is used has been tested for interoperability with users' assistive technology in the human language(s) of the content,

    AND

  2. The [non-web document or software] technology must have accessibility-supported user agents [or other software] that are available to users. This means that at least one of the following four statements is true:

    1. The technology is supported natively in widely-distributed user agents [or other software] that are also accessibility supported (such as HTML and CSS);

      OR

    2. The technology is supported in a widely-distributed plug-in [or other software extension] that is also accessibility supported;

      OR

    3. The content is available in a closed environment, such as a university or corporate network, where the user agent [or other software] required by the technology and used by the organization is also accessibility supported;

      OR

    4. The user agent(s) that support the technology are accessibility supported and are available for download or purchase in a way that:

      • does not cost a person with a disability any more than a person without a disability and

      • is as easy to find and obtain for a person with a disability as it is for a person without disabilities.

Note

[The concepts behind the five Notes and in Understanding Accessibility Supported are applicable to web technologies. The same or similar factors are applicable for non-web technologies.]

ambiguous to users in general

the purpose cannot be determined from the link and all information of the Web page presented to the user simultaneously with the link (i.e., readers without disabilities would not know what a link would do until they activated it)

Applying “ambiguous to users in general” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web page” with “non-web document or software”.

With this substitution, it would read:

ambiguous to users in general

the purpose cannot be determined from the link and all information of the [non-web document or software] presented to the user simultaneously with the link (i.e., readers without disabilities would not know what a link would do until they activated it)

Example: The word guava in the following sentence “One of the notable exports is guava” is a link. The link could lead to a definition of guava, a chart listing the quantity of guava exported or a photograph of people harvesting guava. Until the link is activated, all readers are unsure and the person with a disability is not at any disadvantage.

assistive technology

hardware and/or software that acts as a user agent, or along with a mainstream user agent, to provide functionality to meet the requirements of users with disabilities that go beyond those offered by mainstream user agents

Note 1

Functionality provided by assistive technology includes alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible).

Note 2

Assistive technologies often communicate data and messages with mainstream user agents by using and monitoring APIs.

Note 3

The distinction between mainstream user agents and assistive technologies is not absolute. Many mainstream user agents provide some features to assist individuals with disabilities. The basic difference is that mainstream user agents target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The mainstream user agent may provide important functionality to assistive technologies like retrieving Web content from program objects or parsing markup into identifiable bundles.

Applying “assistive technology” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “acts as a user agent” with “acts stand-alone”, replacing “a mainstream user agent” with “mainstream information and communication technologies (ICT)” (later “mainstream ICT])”, and replacing “Web content” with “content”.

With these substitutions, it would read:

assistive technology (as used in this document)

hardware and/or software that acts [stand-alone], or along with [mainstream information and communication technologies (ICT)], to provide functionality to meet the requirements of users with disabilities that go beyond those offered by [mainstream ICT]

Note 1

Functionality provided by assistive technology includes alternative presentations (e.g., as synthesized speech or magnified content), alternative input methods (e.g., voice), additional navigation or orientation mechanisms, and content transformations (e.g., to make tables more accessible).

Note 2

Assistive technologies often communicate data and messages with [mainstream ICTs] by using and monitoring APIs.

Note 3

The distinction between [mainstream ICTs] and assistive technologies is not absolute. Many [mainstream ICTs] provide some features to assist individuals with disabilities. The basic difference is that [mainstream ICTs] target broad and diverse audiences that usually include people with and without disabilities. Assistive technologies target narrowly defined populations of users with specific disabilities. The assistance provided by an assistive technology is more specific and appropriate to the needs of its target users. The [mainstream ICT] may provide important functionality to assistive technologies like retrieving [content] from program objects or parsing markup into identifiable bundles.

Example: Assistive technologies that are important in the context of this document include the following:

  • screen magnifiers, and other visual reading assistants, which are used by people with visual, perceptual and physical print disabilities to change text font, size, spacing, color, synchronization with speech, etc. in order to improve the visual readability of rendered text and images;
  • screen readers, which are used by people who are blind to read textual information through synthesized speech or braille;
  • text-to-speech software, which is used by some people with cognitive, language, and learning disabilities to convert text into synthetic speech;
  • speech recognition software, which may be used by people who have some physical disabilities;
  • alternative keyboards, which are used by people with certain physical disabilities to simulate the keyboard (including alternate keyboards that use head pointers, single switches, sip/puff and other special input devices.);
  • alternative pointing devices, which are used by people with certain physical disabilities to simulate mouse pointing and button activations.

changes of context

major changes that, if made without user awareness, can disorient users who are not able to view the entire page simultaneously

Changes in context include changes of:

  1. user agent;
  2. viewport;
  3. focus;
  4. content that changes the meaning of the Web page
Note

A change of content is not always a change of context. Changes in content, such as an expanding outline, dynamic menu, or a tab control do not necessarily change the context, unless they also change one of the above (e.g., focus).

Applying “changes of context” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web page” and “page” with “non-web document or content presented by software”.

With this substitution, it would read:

changes of context

major changes in the content of the [non-web document or content presented by software] that, if made without user awareness, can disorient users who are not able to view the entire non-web document or content presented by software] simultaneously

Changes in context include changes of:

  1. user agent;

  2. viewport;

  3. focus;

  4. content that changes the meaning of the [non-web document or content presented by software].

Note

A change of content is not always a change of context. Changes in content, such as an expanding outline, dynamic menu, or a tab control do not necessarily change the context, unless they also change one of the above (e.g., focus).

Example: Opening a new window, moving focus to a different component, going to a new page (including anything that would look to a user as if they had moved to a new page) or significantly re-arranging the content of a page are examples of changes of context.

Note 1

A change in the user agent might include bringing up a new window, or might be a significant change in the menus and/or toolbars that are displayed and available for interacting with some portion of the document.

Cognitive function test

[New]

A task that requires the user to remember, manipulate, or transcribe information. Examples include, but are not limited to:

  • memorization, such as remembering a username, password, set of characters, images, or patterns. The common identifiers name, e-mail, and phone number are not considered cognitive function tests as they are personal to the user and consistent across Web sites;
  • transcription, such as typing in characters;
  • use of correct spelling;
  • performance of calculations;
  • solving of puzzles.
Applying “cognitive function test” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2.2 glossary, replacing “Web sites” with “Web sites, non-web documents, and software”.

With this substitution, it would read:

cognitive function test

A task that requires the user to remember, manipulate, or transcribe information. Examples include, but are not limited to:

memorization, such as remembering a username, password, set of characters, images, or patterns. The common identifiers name, e-mail, and phone number are not considered cognitive function tests as they are personal to the user and consistent across [Web sites, non-web documents, and software];

  • transcription, such as typing in characters;
  • use of correct spelling;
  • performance of calculations;
  • solving of puzzles.

conforming alternate version

version that

  1. conforms at the designated level, and
  2. provides all of the same information and functionality in the same human language, and
  3. is as up to date as the non-conforming content, and
  4. for which at least one of the following is true:

    1. the conforming version can be reached from the non-conforming page via an accessibility-supported mechanism, or
    2. the non-conforming version can only be reached from the conforming version, or
    3. the non-conforming version can only be reached from a conforming page that also provides a mechanism to reach the conforming version
Note 1

In this definition, "can only be reached" means that there is some mechanism, such as a conditional redirect, that prevents a user from "reaching" (loading) the non-conforming page unless the user had just come from the conforming version.

Note 2

The alternate version does not need to be matched page for page with the original (e.g., the conforming alternate version may consist of multiple pages).

Note 3

If multiple language versions are available, then conforming alternate versions are required for each language offered.

Note 4

Alternate versions may be provided to accommodate different technology environments or user groups. Each version should be as conformant as possible. One version would need to be fully conformant in order to meet conformance requirement 1.

Note 5

The conforming alternative version does not need to reside within the scope of conformance, or even on the same Web site, as long as it is as freely available as the non-conforming version.

Note 6

Alternate versions should not be confused with supplementary content, which support the original page and enhance comprehension.

Note 7

Setting user preferences within the content to produce a conforming version is an acceptable mechanism for reaching another version as long as the method used to set the preferences is accessibility supported.

See Understanding Conforming Alternate Versions

Applying “conforming alternate version” to Non-Web Documents and Software

The guidance in this document does not use the term “conforming alternate version”.

See the section Comments on Conformance.

content

information and sensory experience to be communicated to the user by means of a user agent, including code or markup that defines the content's structure, presentation, and interactions

Applying “content (Web Content)” to Non-Web Documents and Software

See the guidance on content in the Key Terms section.

contrast ratio

(L1 + 0.05) / (L2 + 0.05), where

Note 1

Contrast ratios can range from 1 to 21 (commonly written 1:1 to 21:1).

Note 2

Because authors do not have control over user settings as to how text is rendered (for example font smoothing or anti-aliasing), the contrast ratio for text can be evaluated with anti-aliasing turned off.

Note 3

For the purpose of Success Criteria 1.4.3 and 1.4.6, contrast is measured with respect to the specified background over which the text is rendered in normal usage. If no background color is specified, then white is assumed.

Note 4

Background color is the specified color of content over which the text is to be rendered in normal usage. It is a failure if no background color is specified when the text color is specified, because the user's default background color is unknown and cannot be evaluated for sufficient contrast. For the same reason, it is a failure if no text color is specified when a background color is specified.

Note 5

When there is a border around the letter, the border can add contrast and would be used in calculating the contrast between the letter and its background. A narrow border around the letter would be used as the letter. A wide border around the letter that fills in the inner details of the letters acts as a halo and would be considered background.

Note 6

WCAG conformance should be evaluated for color pairs specified in the content that an author would expect to appear adjacent in typical presentation. Authors need not consider unusual presentations, such as color changes made by the user agent, except where caused by authors' code.

Applying “contrast ratio” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.

Because relative luminance is defined such that it cannot directly apply to hardware, please note the text in the introduction which reads: “This document does not comment on hardware aspects of products, non-UI aspects of platforms, or the application of WCAG 2 for user-interface components as a category, because the basic constructs on which the WCAG 2 and / or its conformance are built do not apply to these.”

CSS pixel

visual angle of about 0.0213 degrees

A CSS pixel is the canonical unit of measure for all lengths and measurements in CSS. This unit is density-independent, and distinct from actual hardware pixels present in a display. User agents and operating systems should ensure that a CSS pixel is set as closely as possible to the CSS Values and Units Module Level 3 reference pixel [css3-values], which takes into account the physical dimensions of the display and the assumed viewing distance (factors that cannot be determined by content authors).

Applying “CSS pixel” to Non-Web Documents and Software
Editor's note
The WCAG2ICT task force has added additional notes around how “CSS pixel” should be applied to non-web software. These changes were made in response to public comments received on the previous draft.

This applies directly as written and as described in the WCAG 2 glossary.

Note 1
Non-web software and its accompanying platform software do not use CSS pixel measurements. Therefore, use platform-defined density-independent pixel measurements which approximate the CSS reference pixel. Examples of platform-defined density-independent pixel measurements include: points (pt) for iOS and macOS, density-independent pixels (dp) for Android, and effective pixels (epx) for Windows.
Note 2
Examples where a density-independent pixel may not be defined in the platform:
  • Software designed for specific hardware, such as kiosks or office equipment, where the author knows the physical screen size and, potentially, the pixel density.
  • Software, such as streaming apps on smart TV platforms or similar software, where the author may lack information about the physical screen size but may know an appropriate viewing distance or viewing angle.

When there is no platform-defined density-independent pixel measurement, the reference pixel size can be approximated in the following manner:

  • Determine a viewing distance that matches the use case and display type. For instance, in the case of a touchscreen, the viewing distance is normally less than the length of an arm, typically around 28 inches (71 cm).
  • Calculate the size of the reference pixel: Divide the viewing distance by 2688. The number 2688 is obtained by dividing 28 inches (arm's length) by the derived reference pixel size (1/96 inch).
Note 3
Most software and devices are usable at more than one viewing distance. However, only viewing distances that are plausible for the product can be considered an appropriate approximation for the reference pixel. For example, in software designed for use with a touchscreen, a visual-angle pixel longer than 0.11 inch (0.28 mm) would not be plausible, because this would signify a viewing distance of more than arm’s length.
Note 4
People with low vision often use devices at less than the standard viewing distance. However, basing the density-independent pixel on a typical viewing distance provides a balance of benefits for users with disabilities. If a longer viewing distance were chosen as the basis for the density-independent pixel, the viewport would be measured with a smaller number of larger pixels, causing Success Criterion 1.4.10 Reflow to be less stringent. If a shorter viewing distance were chosen, user interface components would be measured with a larger number of smaller pixels, causing some success criteria, such as 2.5.8 Target Size, to be less stringent.

down-event

platform event that occurs when the trigger stimulus of a pointer is depressed

The down-event may have different names on different platforms, such as "touchstart" or "mousedown".

From the WCAG 2 definition for down-event:

Applying “down-event” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.  

Note

The down-event may have different names on different platforms. For example ["PointerPressed” or “mousedown”].

general flash and red flash thresholds

a flash or rapidly changing image sequence is below the threshold (i.e., content passes) if any of the following are true:

  1. there are no more than three general flashes and / or no more than three red flashes within any one-second period; or
  2. the combined area of flashes occurring concurrently occupies no more than a total of .006 steradians within any 10 degree visual field on the screen (25% of any 10 degree visual field on the screen) at typical viewing distance

where:

  • A general flash is defined as a pair of opposing changes in relative luminance of 10% or more of the maximum relative luminance (1.0) where the relative luminance of the darker image is below 0.80; and where "a pair of opposing changes" is an increase followed by a decrease, or a decrease followed by an increase, and
  • A red flash is defined as any pair of opposing transitions involving a saturated red

Exception: Flashing that is a fine, balanced, pattern such as white noise or an alternating checkerboard pattern with "squares" smaller than 0.1 degree (of visual field at typical viewing distance) on a side does not violate the thresholds.

Note 1

For general software or Web content, using a 341 x 256 pixel rectangle anywhere on the displayed screen area when the content is viewed at 1024 x 768 pixels will provide a good estimate of a 10 degree visual field for standard screen sizes and viewing distances (e.g., 15-17 inch screen at 22-26 inches). This resolution of 75 - 85 ppi is known to be lower, and thus more conservative than the nominal CSS pixel resolution of 96 ppi in CSS specifications. Higher resolutions displays showing the same rendering of the content yield smaller and safer images so it is lower resolutions that are used to define the thresholds.

Note 2

A transition is the change in relative luminance (or relative luminance/color for red flashing) between adjacent peaks and valleys in a plot of relative luminance (or relative luminance/color for red flashing) measurement against time. A flash consists of two opposing transitions.

Note 3

The new working definition in the field for "pair of opposing transitions involving a saturated red" (from WCAG 2.2) is a pair of opposing transitions where, one transition is either to or from a state with a value R/(R + G + B) that is greater than or equal to 0.8, and the difference between states is more than 0.2 (unitless) in the CIE 1976 UCS chromaticity diagram. [ISO_9241-391]

Note 4

Tools are available that will carry out analysis from video screen capture. However, no tool is necessary to evaluate for this condition if flashing is less than or equal to 3 flashes in any one second. Content automatically passes (see #1 and #2 above).

Applying “general flash and red flash thresholds” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.

Note

Because this deals with relative luminance and not luminance, it can only be applied to information on a display, not to hardware sources of light.

input error

information provided by the user that is not accepted

Note

This includes:

  1. Information that is required by the Web page but omitted by the user
  2. Information that is provided by the user but that falls outside the required data format or values
Applying “input error” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web page” with “non-web document or software”.

With this substitution, it would read:

input error

information provided by the user that is not accepted

Note
This includes:
  1. Information that is required by the [non-web document or software] but omitted by the user

  2. Information that is provided by the user but that falls outside the required data format or values

keyboard interface

interface used by software to obtain keystroke input

Note 1

A keyboard interface allows users to provide keystroke input to programs even if the native technology does not contain a keyboard.

Note 2

Operation of the application (or parts of the application) through a keyboard-operated mouse emulator, such as MouseKeys, does not qualify as operation through a keyboard interface because operation of the program is through its pointing device interface, not through its keyboard interface.

Applying “keyboard interface” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.

Please see the note in the Applying SC 2.1.1 Keyboard section that uses this definition and which reads: “This does not imply that software always needs to directly support a keyboard or ‘keyboard interface’. Nor does it imply that software always needs to provide a soft keyboard. Underlying platform software may provide device independent input services to applications that enable operation via a keyboard. Software that supports operation via such platform device independent services would be operable by a keyboard and would comply.”

keyboard shortcut

alternative means of triggering an action by the pressing of one or more keys

Applying “keyboard shortcut” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.

Note

A key command issued by a long press of a key (2 seconds or more) and other accessibility features provided by the platform are not considered a keyboard shortcut. Such commands often occur when there are limited keys, or no modifier keys, present on a device.

label

text or other component with a text alternative that is presented to a user to identify a component within Web content

Note 1

A label is presented to all users whereas the name may be hidden and only exposed by assistive technology. In many (but not all) cases the name and the label are the same.

Note 2

The term label is not limited to the label element in HTML.

Applying “label” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web Content” with “content” and adding “or by accessibility features of software” after “assistive technology” in Note 1.

With this substitution, it would read:

label

text or other component with a text alternative that is presented to a user to identify a component within [content]

Note 1

A label is presented to all users whereas the name may be hidden and only exposed by assistive technology [or by accessibility features of software]. In many (but not all) cases the name and the label are the same.

Note 2

The term label is not limited to the label element in HTML.

name

text by which software can identify a component within Web content to the user

Note 1

The name may be hidden and only exposed by assistive technology, whereas a label is presented to all users. In many (but not all) cases, the label and the name are the same.

Note 2

This is unrelated to the name attribute in HTML.

Applying “name” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web content” with “content” and adding “or by accessibility features of software” after “assistive technology” in Note 1.

With this substitution, it would read:

name

text by which software can identify a component within [content] to the user

Note 1

The name may be hidden and only exposed by assistive technology [or by accessibility features of software], whereas a label is presented to all users. In many (but not all) cases, the label and the name are the same.

Note 2

This is unrelated to the name attribute in HTML.

Note 1

“AccessibleName” (or the corresponding term used in different APIs) of the Accessibility API of the platform is an example of such a name.

perimeter

[New]

continuous line forming the boundary of a shape not including shared pixels, or the minimum bounding box, whichever is shortest.

Applying “perimeter” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing "CSS pixel" with "platform-defined density-independent pixel".

With this substitution, it would read:

perimeter

continuous line forming the boundary of a shape not including shared pixels, or the minimum bounding box, whichever is shortest.

Example: The perimeter calculation for a 2 [platform-defined density-independent pixel] perimeter around a rectangle is 4h+4w, where h is the height and w is the width. For a 2 [platform-defined density-independent pixel] perimeter around a circle it is 4𝜋r.

Note

In technologies where CSS is not used, the definition of 'CSS pixel' applies as described in Applying “CSS pixel” to Non-Web Documents and Software.

programmatically determined

determined by software from author-supplied data provided in a way that different user agents, including assistive technologies, can extract and present this information to users in different modalities

Applying “programmatically determined” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “user agents, including assistive technologies” with “assistive technologies and accessibility features of software” and adding and “accessibility features of software” after “assistive technology”.

With this substitution, it would read:

programmatically determined (programmatically determinable)

determined by software from author-supplied data provided in a way that different [assistive technologies and accessibility features of software], can extract and present this information to users in different modalities

Example 1: Determined in a markup language from elements and attributes that are accessed directly by commonly available assistive technology [and accessibility features of software].

Example 2: Determined from technology-specific data structures in a non-markup language and exposed to assistive technology [and accessibility features of software] via an accessibility API that is supported by commonly available assistive technology [and accessibility features of software].

Note

Software typically enables content to be programmatically determined through the use of accessibility services of platform software. Non-web documents typically enable content to be programmatically determined through the use of accessibility services of the user agent.

programmatically set

set by software using methods that are supported by user agents, including assistive technologies

Applying “programmatically set” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “user agents, including assistive technologies” with “assistive technologies and accessibility features of software”.

With this substitution, it would read:

programmatically set

set by software using methods that are supported by [assistive technologies and accessibility features of software]

Note

Software typically enables content to be programmatically determined through the use of accessibility services of platform software. Non-web documents typically enable content to be programmatically determined through the use of accessibility services of the user agent.

relative luminance

the relative brightness of any point in a colorspace, normalized to 0 for darkest black and 1 for lightest white

Note 1

For the sRGB colorspace, the relative luminance of a color is defined as L = 0.2126 * R + 0.7152 * G + 0.0722 * B where R, G and B are defined as:

  • if RsRGB <= 0.04045 then R = RsRGB/12.92 else R = ((RsRGB+0.055)/1.055) ^ 2.4
  • if GsRGB <= 0.04045 then G = GsRGB/12.92 else G = ((GsRGB+0.055)/1.055) ^ 2.4
  • if BsRGB <= 0.04045 then B = BsRGB/12.92 else B = ((BsRGB+0.055)/1.055) ^ 2.4

and RsRGB, GsRGB, and BsRGB are defined as:

  • RsRGB = R8bit/255
  • GsRGB = G8bit/255
  • BsRGB = B8bit/255

The "^" character is the exponentiation operator. (Formula taken from [SRGB].)

Note 2

Before May 2021 the value of 0.04045 in the definition was different (0.03928). It was taken from an older version of the specification and has been updated. It has no practical effect on the calculations in the context of these guidelines.

Note 3

Almost all systems used today to view Web content assume sRGB encoding. Unless it is known that another color space will be used to process and display the content, authors should evaluate using sRGB colorspace. If using other color spaces, see Understanding Success Criterion 1.4.3.

Note 4

If dithering occurs after delivery, then the source color value is used. For colors that are dithered at the source, the average values of the colors that are dithered should be used (average R, average G, and average B).

Note 5

Tools are available that automatically do the calculations when testing contrast and flash.

Note 6

A separate page giving the relative luminance definition using MathML to display the formulas is available.

Applying “relative luminance” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web content” with “content”.

With this substitution, it would read:

relative luminance

the relative brightness of any point in a colorspace, normalized to 0 for darkest black and 1 for lightest white

Note 1
For the sRGB colorspace, the relative luminance of a color is defined as L = 0.2126 \* **R** + 0.7152 \* **G** + 0.0722 \* **B** where **R**, **G** and **B** are defined as:
  • if RsRGB <= 0.03928 then R = RsRGB/12.92 else R = ((RsRGB+0.055)/1.055) ^ 2.4
  • if GsRGB <= 0.03928 then G = GsRGB/12.92 else G = ((GsRGB+0.055)/1.055) ^ 2.4
  • if BsRGB <= 0.03928 then B = BsRGB/12.92 else B = ((BsRGB+0.055)/1.055) ^ 2.4

and RsRGB, GsRGB, and BsRGB are defined as:

  • RsRGB = R8bit/255
  • GsRGB = G8bit/255
  • BsRGB = B8bit/255

The “^” character is the exponentiation operator. (Formula taken from [sRGB]).

Note 2
Before May 2021 the value of 0.04045 in the definition was different (0.03928). It was taken from an older version of the specification and has been updated. It has no practical effect on the calculations in the context of these guidelines.
Note 3

Almost all systems used today to view [content] assume sRGB encoding. Unless it is known that another color space will be used to process and display the content, authors should evaluate using sRGB colorspace. If using other color spaces, see Understanding Success Criterion 1.4.3.

Note 4

If dithering occurs after delivery, then the source color value is used. For colors that are dithered at the source, the average values of the colors that are dithered should be used (average R, average G, and average B).

Note 5

Tools are available that automatically do the calculations when testing contrast and flash.

Note 1
Because relative luminance is defined such that it cannot directly apply to hardware, please note the text in the introduction which reads: “This document does not comment on hardware aspects of products, non-UI aspects of platforms, or the application of WCAG 2 for user-interface components as a category, because the basic constructs on which the WCAG 2 and / or its conformance are built do not apply to these.”

role

text or number by which software can identify the function of a component within Web content

Applying “role” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “Web content” with “content”.

With this substitution, it would read:

role

text or number by which software can identify the function of a component within [content]

Example: A number that indicates whether an image functions as a hyperlink, command button, or check box.

Note

“AccessibleRole” (or the corresponding term used in different APIs) of the Accessibility API of the platform is an example of such a role.

same functionality

same result when used

Applying “same functionality” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, adding a second example (and numbering the first).

With these substitutions, it would read:

same functionality

same result when used

Example 1: A submit “search” button on one web page and a “find” button on another web page may both have a field to enter a term and list topics in the Web site related to the term submitted. In this case, they would have the same functionality but would not be labeled consistently.

Example 2: A ribbon icon that saves the document that looks like an arrow pointing into a folder in one case, and an arrow pointing into a hard drive in another. In this case as well, they would have the same functionality but would not be labeled consistently.

satisfies a success criterion

the success criterion does not evaluate to 'false' when applied to the page

Applying “satisfies a success criterion” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “page” with “non-web document or software”.

With this substitution, it would read:

satisfies a success criterion

the success criterion does not evaluate to 'false' when applied to the [non-web document or software]

Note

Though WCAG2ICT and WCAG 2 don't use this exact phrase, in this document there are variations of the phrase that use this definition. See "success criteria is satisfied" in Section 6 Comments on Conformance and "satisfy any success criterion" in the notes for the definition of set of software programs.

set of web pages

collection of web pages that share a common purpose and that are created by the same author, group or organization

Note

Different language versions would be considered different sets of Web pages.

Applying “set of Web pages” to Non-Web Documents and Software

See the guidance on set of documents and set of software programs in the Key Terms section.

Note

For success criteria that use the term “set of web pages”, either explicitly or implicitly (2.4.1, 2.4.5, 3.2.3, and 3.2.4), simply substitute "set of non-web documents" and "set of software programs" when applying this to non-web technologies.

structure

  1. The way the parts of a Web page are organized in relation to each other; and
  2. The way a collection of Web pages is organized
Applying “structure” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “a Web page” with “non-web documents or software” and replacing “collection of Web pages” with “set of documents or set of software programs”.

With these substitutions, it would read:

structure
  1. The way the parts of [non-web documents or software] are organized in relation to each other; and

  2. The way a [set of documents or set of software programs] is organized

Note

See the guidance on sets of documents and sets of software programs in the Key Terms section.

style property

property whose value determines the presentation (e.g. font, color, size, location, padding, volume, synthesized speech prosody) of content elements as they are rendered (e.g. onscreen, via loudspeaker, via braille display) by user agents

Style properties can have several origins:

  • User agent default styles: The default style property values applied in the absence of any author or user styles. Some web content technologies specify a default rendering, others do not;
  • Author styles: Style property values that are set by the author as part of the content (e.g. in-line styles, author style sheets);
  • User styles: Style property values that are set by the user (e.g. via user agent interface settings, user style sheets)
Applying “style property” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “user agent(s)” with “user agent(s) or platform software”, "web content" with "content", replacing "in-line styles, author style sheets" with "programmatically-set styles", and replacing "user agent interface settings, user style sheets" with "user agent, platform software or other software settings".

With these substitutions, it would read:

style property

property whose value determines the presentation (e.g. font, color, size, location, padding, volume, synthesized speech prosody) of content elements as they are rendered (e.g. onscreen, via loudspeaker, via braille display) by [user agents or platform software]

Style properties can have several origins:

  • [User agent or platform software] default styles: The default style property values applied in the absence of any author or user styles. Some [content] technologies specify a default rendering, others do not;
  • Author styles: Style property values that are set by the author as part of the content (e.g. [programmatically-set styles]);
  • User styles: Style property values that are set by the user (e.g. via [user agent, platform software or other software] interface settings)

target

region of the display that will accept a pointer action, such as the interactive area of a user interface component

Note

If two or more targets are overlapping, the overlapping area should not be included in the measurement of the target size, except when the overlapping targets perform the same action or open the same page.

Applying “target” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “page” with “non-web document or content presented by software”.

With this substitution, it would read:

target

region of the display that will accept a pointer action, such as the interactive area of a user interface component

Note

If two or more targets are overlapping, the overlapping area should not be included in the measurement of the target size, except when the overlapping targets perform the same action or open the same [non-web document or content presented by software].

technology

mechanism for encoding instructions to be rendered, played or executed by user agents

Note 1

As used in these guidelines "Web Technology" and the word "technology" (when used alone) both refer to Web Content Technologies.

Note 2

Web content technologies may include markup languages, data formats, or programming languages that authors may use alone or in combination to create end-user experiences that range from static Web pages to synchronized media presentations to dynamic Web applications.

Applying “technology” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “web content” with “non-web document or software”, “user agents” with “user agents or other software”, removing the notes, and replacing the example with “Example: Some common examples of non-web document and software technologies include ODF, OOXML, Java, and C++.”

With these substitutions, it would read:

technology (**[non-web document or software]**)

mechanism for encoding instructions to be rendered, played or executed by [user agents or other software].

Example: Some common examples of [non-web document and software technologies include ODF, OOXML, Java, and C++].

up-event

platform event that occurs when the trigger stimulus of a pointer is released

The up-event may have different names on different platforms, such as "touchend" or "mouseup".

Applying “up-event” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.  

Note

The up-event may have different names on different platforms, such as [“PointerReleased” or “mouseup”].

user agent

any software that retrieves and presents Web content for users

Applying “user agent” to Non-Web Documents and Software

See the guidance on user agent in the Key Terms section.

user interface component

a part of the content that is perceived by users as a single control for a distinct function

Note 1

Multiple user interface components may be implemented as a single programmatic element. "Components" here is not tied to programming techniques, but rather to what the user perceives as separate controls.

Note 2

User interface components include form elements and links as well as components generated by scripts.

Note 3

What is meant by "component" or "user interface component" here is also sometimes called "user interface element".

Applying “user interface component” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing the example with “Example: A software program has 2 controls: a text field for entering a file name and a drop down list box for choosing a folder. Each is a user interface component with a name that is settable by the software.”

With this substitution, it would read:

user interface component

a part of the content that is perceived by users as a single control for a distinct function

Note 1

Multiple user interface components may be implemented as a single programmatic element. "Components" here is not tied to programming techniques, but rather to what the user perceives as separate controls.

Note 2

User interface components include form elements and links as well as components generated by scripts.

Note 3

What is meant by "component" or "user interface component" here is also sometimes called "user interface element".

Example: A software program has 2 controls: a text field for entering a file name and a drop down list box for choosing a folder. Each is a user interface component with a name that is settable by the software.

viewport

object in which the user agent presents content

Note 1

The user agent presents content through one or more viewports. Viewports include windows, frames, loudspeakers, and virtual magnifying glasses. A viewport may contain another viewport (e.g., nested frames). Interface components created by the user agent such as prompts, menus, and alerts are not viewports.

Note 2

This definition is based on User Agent Accessibility Guidelines 1.0 Glossary [UAAG10].

Applying “viewport” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary, replacing “user agent” with “software”.

With this substitution, it would read:

viewport

object in which the [software] presents content

Note 1

The [software] presents content through one or more viewports. Viewports include windows, frames, loudspeakers, and virtual magnifying glasses. A viewport may contain another viewport (e.g., nested frames). Interface components created by the [software] such as prompts, menus, and alerts are not viewports.

Note 2

Web page

a non-embedded resource obtained from a single URI using HTTP plus any other resources that are used in the rendering or intended to be rendered together with it by a user agent

Note 1

Although any "other resources" would be rendered together with the primary resource, they would not necessarily be rendered simultaneously with each other.

Note 2

For the purposes of conformance with these guidelines, a resource must be "non-embedded" within the scope of conformance to be considered a Web page.

Applying “Web Page” to Non-Web Documents and Software

This applies directly as written and as described in the WCAG 2 glossary.

Note

For those success criteria that use the term “web page”, WCAG2ICT provides specific replacement term(s) for “Web page”.

Privacy Considerations

This section is non-normative.

This Working Group Note does not introduce any new privacy considerations. Horizontal Review Groups are encouraged to provide further feedback during the Horizontal Review process.

Security Considerations

This section is non-normative.

This Working Group Note does not introduce any new security considerations. Horizontal Review Groups are encouraged to provide further feedback during the Horizontal Review process.

A. Success Criteria Problematic for Closed Functionality

Editor's note
This section has been updated to include new WCAG 2.1 and 2.2 criteria that are problematic for Closed Functionality as well as remove obsolete criteria. The Task Force has also updated some of the existing content in this section to reflect new insights learned since the 2013 WCAG2ICT Note and to address public comments received on the previous draft.

There are success criteria that can be problematic for developers of ICT with closed functionality. Some criteria discuss making information available in text (which can be read by assistive technologies), making it “programmatically determinable” (rendered by a user agent and readable by assistive technologies), or doing something else to make content compatible with assistive technologies. Where ICT with closed functionality doesn’t support use of assistive technology or the platform is not sophisticated enough to have an accessibility API, providing equivalent information and operation through another mechanism, such as functions built into the software that behave like assistive technology, would help meet the intent of these success criteria.

Other success criteria would apply to systems with closed functionality either if they are partially closed or if they allow for the connection of some types of devices. As an example, Success Criterion 2.1.1 Keyboard would apply to systems which are closed to screen readers, but have a physical keyboard, a connector for standard keyboards, or allow the installation of alternate keyboards. While these criteria, as written, are not always applicable to closed functionality, most of them can inform and aid development of built-in features needed to make products with closed functionality accessible.

For non-web software on products with closed functionality, those who implement this document (WCAG2ICT) should consider the applicability of individual WCAG 2 success criteria on a criterion-by-criterion basis. Alternate accessibility provisions might be needed to cover the user needs addressed by the following success criteria:

B. Background on Text / Command-line / Terminal Applications and Interfaces

B.1 How text interfaces are realized

The interface of a text application is realized through a server application directing which characters should be placed on the screen, along with either a hardware terminal or a terminal application that displays the characters. The client terminal application for text applications is analogous to a web user agent for web pages. Also, like web applications, text applications may execute primarily on a remote server or execute locally.

Some text applications render like a TeleTYpewriter (TTY); their output is always appended, like an ever-growing file. Such text applications are often called “command-line applications” or occasionally “TTY-applications”, and their output can optionally be redirected to a file for later review. Others explicitly place text into a matrix of fixed width character cells on a screen (sometimes with specific foreground and background colors).

Historically, input to the text application itself is provided exclusively through a keyboard interface, though Automatic Speech Recognition (ASR) based voice input is sometimes now an alternative option - especially on mobile devices.

B.2 How text applications have been made accessible via assistive technology

Strategies for making text applications accessible through assistive technology involve two key tasks: (1) obtaining all of the text displayed in the interface, and (2) performing an analysis on that text to detect screen updates and attempt to discern structural elements.

For example, a text application screen reader might directly access the matrix of character cells in the interface and provide a screen review mechanism for the user to review that matrix of characters (by sending the output to synthetic speech and/or a braille display). Alternately, a text application screen reader might directly consume the output rendered (perhaps by acting as its own terminal application or by analyzing the “TTY” output). A text application screen reader might also attempt to analyze the spacing and layout of the text in the matrix, to provide features such as reading columns of text in a multi-column layout; discerning headers through analysis of line spacing, indentation, and capitalization; and discerning input fields or user interface components by scanning for the use of inverse video, for text appearing in brackets, or for text from the character graphics codepage (ASCII codes greater than ‘0x7F’). Some of this analysis might also be done through the use of filter tools that transform the output of a program (e.g., through reformatting “TTY” output rendered to a file or as direct input to a filter tool).

Similarly, a text application screen magnifier would gain access to the matrix of character cells to magnify them or re-display them in a larger font. It would scan for screen refreshes and updates and then apply heuristics to what had changed in order to decide what sub-matrix of character cells should appear in a magnified view. It would also scan for inverse video and a moving text cursor to track text being input by the user (and might combine the text matrix scanning with scanning of the keyboard input to match user input to what is appearing on the screen).

B.3 Applying WCAG 2 to text applications

To apply WCAG to text applications, it is necessary to apply the glossary terms accessibility supported and programmatically determined in the context of how text applications are rendered and the history of assistive technologies that made them accessible.

As noted above, in a text interface the terminal application renders the characters on the screen, just as a Web browser typically renders content for a Web application. As an example, for success criterion 1.4.4 Resize Text, a text application could achieve 200 percent resizing when the terminal application client that is rendering it has this capability (cf. WCAG 2 Technique G142 Using a technology that has commonly-available user agents that support zoom). Many web pages and web applications use this approach to meet success criterion 1.4.4 Resize Text through no explicit action of their own.

A similar approach could also be used for success criterion 1.4.3 Contrast (minimum) (cf. WCAG 2 Technique G148: Not specifying background color, not specifying text color, and not using technology features that change those defaults): relying on the terminal application client to render the text with sufficient contrast against the background. In fact, many terminal applications allow the user to force all text to share a single user-chosen foreground color (and a single user-chosen background color), overriding the text application's specified colors to meet the user's desires or needs.

Since many assistive technology analysis techniques depend upon discerning the location of the text input cursor, terminal application use of “soft cursors” and “highlight bars” may bypass those analysis techniques and cause failures of success criteria.

Note 1
It is outside of the scope of this document to define WCAG techniques for non-web ICT. These examples are simply illustrations of how WCAG 2 success criteria can be applied to this class of non-web software applications.

The way to think about "accessibility supported" and "programmatically determined" may seem a little different for text applications, but the definitions are unchanged. Unlike the semantic objects of graphical user interfaces and web pages, the output of text-based applications consists of plain text. A terminal emulator acts as the user agent for text-based applications; it might render some content such as escape codes as semantic elements, but otherwise exposes only lines of text to assistive technology. Where assistive technology is able to interpret the text and any semantic objects accurately, the content is "programmatically determinable"—even though no explicit markup was necessarily used to make it so.

Note 2
The terminal application itself is “traditional” non-web software ICT. It is only for the text application that there is a need to take this approach with these glossary terms.

C. Acknowledgements

C.1 Active Participants of the WCAG2ICT Task Force Involved in the Development of this Document

C.2 Participants in the AG Working Group that Actively Reviewed and Contributed

Editor's note
This list will be updated as AG WG reviews and contributions are completed.

C.3 Participants in the APA Working Group that Contributed

Special thanks goes to members of the APA working group that contributed their expertise to updates in the Text / Command-line / Terminal Applications and Interfaces content.

C.4 Other Participants of the WCAG2ICT Task Force

C.5 Previous Contributors

The following people contributed to the development of the 2013 WCAG2ICT Note.

Shadi Abou-Zahra, Bruce Bailey, Judy Brewer, Michael Cooper, Pierce Crowell, Allen Hoffman, Kiran Kaja, Andrew Kirkpatrick, Peter Korn, Alex Li, David MacDonald, Mary Jo Mueller, Loïc Martínez Normand, Mike Pluke, Janina Sajka, Andi Snow-Weaver, Gregg Vanderheiden

C.6 Enabling Funders

This publication has been funded in part by funds from the following organizations:

The content of this publication does not necessarily reflect the views or policies of the Ford Foundation and/or the European Commission, nor does mention of trade names, commercial products, or organizations imply endorsement by the aforementioned organizations.

D. References

D.1 Informative references

[etsi-en-301-549]
ETSI EN 301 549 V2.1.2 (2018-08): Accessibility requirements for ICT products and services. ETSI. August 2018. Published. URL: http://www.etsi.org/deliver/etsi_en/301500_301599/301549/02.01.02_60/en_301549v020102p.pdf
[UNDERSTANDING-WCAG22]
Understanding Web Content Accessibility Guidelines 2.2. URL: https://www.w3.org/WAI/WCAG22/Understanding/
[WCAG20]
Web Content Accessibility Guidelines (WCAG) 2.0. Ben Caldwell; Michael Cooper; Loretta Guarino Reid; Gregg Vanderheiden et al. W3C. 11 December 2008. W3C Recommendation. URL: https://www.w3.org/TR/WCAG20/
[WCAG21]
Web Content Accessibility Guidelines (WCAG) 2.1. Michael Cooper; Andrew Kirkpatrick; Joshue O'Connor; Alastair Campbell. W3C. 21 September 2023. W3C Recommendation. URL: https://www.w3.org/TR/WCAG21/
[WCAG22]
Web Content Accessibility Guidelines (WCAG) 2.2. Michael Cooper; Andrew Kirkpatrick; Alastair Campbell; Rachael Bradley Montgomery; Charles Adams. W3C. 5 October 2023. W3C Recommendation. URL: https://www.w3.org/TR/WCAG22/
[WCAG22-TECHS]
Techniques for WCAG 2.2. URL: https://www.w3.org/WAI/WCAG22/Techniques/