Web Content Accessibility Guidelines
The Web Content Accessibility Guidelines (WCAG) are a standards reference for creating accessible web content. The W3C publishes and periodically updates these standards.
History
Version 1 of the Web Content Accessibility Guidelines was published by the W3C in 1999. It included these recommendations:
- Provide equivalent alternatives to auditory and visual content
- Don't rely on colour alone
- Use markup and style sheets, and do so properly
- Clarify natural language usage
- Create tables that transform gracefully
- Ensure that pages featuring new technologies transform gracefully
- Ensure user control of time sensitive content changes
- Ensure direct accessibility of embedded user interfaces
- Design for device independence
- User interim solutions
- Use W3C technologies and guidelines
- Provide context and orientation information
- Provide clear navigation mechanisms
- Ensure that documents are clear and simple
Version 2.0 was published in 2008. This added categories of compliance, delineated by tests and requirements that align to the above guidelines but in increasingly strict ways. The categories are:
A (lowest)
AA
AAA (highest)
Backwards-compatible additions to this standard were published in 2018 (as version 2.1) and in 2023 (as version 2.2).
WCAG 2.0 was approved as ISO 40500 in 2012.
In the United States, Section 508 was refreshed in 2017 to match WCAG 2.0 AA.
WCAG 3 is currently a draft proposal.
See also
walkthrough of change between WCAG 2.0, 2.1, and 2.2