Understanding Success Criterion 2.5.5: Target Size (Enhanced)

Success Criterion 2.5.5 Target Size (Enhanced) (Level AAA): The size of the target for pointer inputs is at least 44 by 44 CSS pixels except when:

Equivalent
The target is available through an equivalent link or control on the same page that is at least 44 by 44 CSS pixels;
Inline
The target is in a sentence or block of 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 to the information being conveyed.

Intent

The intent of this success criterion is to help users who may have trouble activating a small target because of hand tremors, limited dexterity or other reasons. If the target is too small, it may be difficult to aim at the target. Mice and similar pointing devices can be hard to use for these users, and a larger target will help them greatly in having positive outcomes on the web page.

Touch is particularly problematic as it is an input mechanism with coarse precision. Users lack the same level of fine control as on inputs such as a mouse or stylus. A finger is larger than a mouse pointer, and generally obstructs the user's view of the precise location on the screen that is being touched/activated.

The issue can be further complicated on for responsive/mobile which need to accommodate different types of fine and coarse inputs (e.g. a site that can be accessed both on a traditional desktop/laptop with a mouse, as well as on a tablet or mobile phone with a touch screen).

While this criterion defines a minimum target size, it is recommended that larger sizes are used to reduce the possibility of unintentional actions. This is particularly relevant if any of the following are true:

Benefits

Examples

Related Resources

Resources are for information purposes only, no endorsement implied.

Techniques

Each numbered item in this section represents a technique or combination of techniques that the WCAG Working Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, see Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Each numbered item in this section represents a technique or combination of techniques that theĀ WCAGWorking Group deems sufficient for meeting this Success Criterion. However, it is not necessary to use these particular techniques. For information on using other techniques, seeĀ Understanding Techniques for WCAG Success Criteria, particularly the "Other Techniques" section.

Sufficient Techniques

Select the situation below that matches your content. Each situation includes techniques or combinations of techniques that are known and documented to be sufficient for that situation.

  • Ensuring that touch targets are at least 44 by 44 CSS pixels.
  • Ensuring inline links provide sufficiently large activation target.

Advisory Techniques

Although not required for conformance, the following additional techniques should be considered in order to make content more accessible. Not all techniques can be used or would be effective in all situations.

  • none documented

Failures

The following are common mistakes that are considered failures of this Success Criterion by the WCAG Working Group.

  • Failure of success criterion 2.5.3 and 2.5.4 due to touch target being less than 44 by 44 CSS pixels.

Key Terms

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).

essential

if removed, would fundamentally change the information or functionality of the content, and information and functionality cannot be achieved in another way that would conform

pointer input

input device that can target a specific coordinate (or set of coordinates) on a screen, such as a mouse, pen, or touch contact

See also Pointer Events pointer definition [[!pointerevents]].

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 touch 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.