Although using colors to convey information is helpful, it can not be perceived by all users, especially users with visual impairments.
Table of Contents
Official Requirements
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.
Why is it required?
Color is an important aspect in web design as it enhances the visual appeal of the website, usability, and accessibility. However, some users may not be able to perceive colors as their peers, especially users with color deficiencies. People with partial sight frequently experience limited color vision and even older users may not see color well. Therefore, information should not be conveyed only through color.
How do we fix it?
- Ensure that information conveyed through color differences is also available in text or additional visual cues
- Provide an asterisk or some text at the beginning of the form to indicate that it is a required field
- Use colors that have relative luminance or lightness difference of 3:1 or greater with the text around.
Mistakes to avoid
- Provided text alternative does not convey the information that is conveyed by color differences in the image.
- The link provided is not visible to users with limited color vision
- Required form fields are only conveyed through colors