Understanding Success Criterion 1.4.1: Use of Color

Success Criterion 1.4.1 Use of Color (Level A): Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element.

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.


The intent of this Success Criterion is to ensure that all sighted users can access information that is conveyed by color differences, that is, by the use of color where each color has a meaning assigned to it. If the information is conveyed through color differences in an image (or other non-text format), the color may not be seen by users with color deficiencies. In this case, providing the information conveyed with color through another visual means ensures users who cannot see color can still perceive the information.

Color is an important asset in design of Web content, enhancing its aesthetic appeal, its usability, and its accessibility. However, some users have difficulty perceiving color. People with partial sight often experience limited color vision, and many older users do not see color well. In addition, people using limited-color or monochrome displays and browsers will be unable to access information that is presented only in color.

Examples of information conveyed by color differences: “required fields are red", “error is shown in red", and “Mary's sales are in red, Tom's are in blue". Examples of indications of an action include: using color to indicate that a link will open in a new window or that a database entry has been updated successfully. An example of prompting a response would be: using highlighting on form fields to indicate that a required field had been left blank.


This should not in any way discourage the use of color on a page, or even color coding if it is complemented by other visual indication.


If content is conveyed through the use of colors that differ not only in their hue, but that also have a significant difference in lightness, then this counts as an additional visual distinction, as long as the difference in relative luminance between the colors leads to a contrast ratio of 3:1 or greater. For example, a light green and a dark red differ both by color (hue) and by lightness, so they would pass if the contrast ratio is at least 3:1. Similarly, if content is distinguished by inverting an element's foreground and background colors, this would pass (again, assuming that the foreground and background colors have a sufficient contrast).

However, if content relies on the user's ability to accurately perceive or differentiate a particular color an additional visual indicator will be required regardless of the contrast ratio between those colors. For example, knowing whether an outline is green for valid or red for invalid.


This criterion does not directly address the needs of users with assistive technologies. It aims to ensure that sighted users who cannot distinguish between some colors can still understand content. How information is conveyed to assistive technology users is covered separately in other criteria, including (but not limited to) 1.1.1 Non-text Content, 1.3.1 Info and Relationships, and 4.1.2 Name, Role, Value.

Conversely, even if information that is conveyed by color differences is appropriately conveyed to assistive technologies, it does not necessarily pass this criterion, as sighted users who cannot distinguish between certain color may not necessarily be using any assistive technologies. This criterion requires a visible alternative to color.



Related Resources

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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.

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.

Situation A: If the color of particular words, backgrounds, or other content is used to indicate information:

  1. G14: Ensuring that information conveyed by color differences is also available in text
  2. G205: Including a text cue for colored form control labels
  3. G182: Ensuring that additional visual cues are available when text color differences are used to convey information
  4. G183: Using a contrast ratio of 3:1 with surrounding text and providing additional visual cues on hover for links or controls where color alone is used to identify them

Situation B: If color is used within an image to convey information:

  1. G111: Using color and pattern
  2. G14: Ensuring that information conveyed by color differences is also available in text

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.


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