WCAG
Web Content Accessibility Guidelines—the international technical standard defining how to make web content accessible to people with disabilities. Provides testable success criteria organized by level (A, AA, AAA).
Definition: Web Content Accessibility Guidelines—the international technical standard defining how to make web content accessible to people with disabilities. Provides testable success criteria organized by level (A, AA, AAA).
WCAG (Web Content Accessibility Guidelines) is the primary international standard for web accessibility, published by the World Wide Web Consortium (W3C).
Purpose
WCAG provides a shared language that allows researchers to translate a user's struggle into a precise, actionable instruction for an engineer.
Example translation:
- User observation: "The user couldn't find the submit button"
- Developer-ready recommendation: "The Submit button is missing a proper ARIA label, violating WCAG Success Criterion 4.1.2"
Conformance Levels
WCAG defines three levels of conformance:
| Level | Description |
|---|---|
| A | Minimum accessibility; addresses the most critical barriers |
| AA | Addresses major barriers; the most common legal requirement |
| AAA | Highest level; not always achievable for all content |
The Four Principles (POUR)
WCAG is organized around four principles—content must be:
- Perceivable: Users must be able to perceive the information
- Operable: Users must be able to operate the interface
- Understandable: Information and operation must be understandable
- Robust: Content must be robust enough to work with assistive technologies
Using WCAG in Research
While observing a real person interact with your product is irreplaceable, your findings become infinitely more powerful when connected to WCAG success criteria.
Related Terms
Accessibility
The practice of designing products usable by as many people as possible, including those with permanent, temporary, or situational disabilities. Often abbreviated as a11y.
Usability
Per ISO 9241-11: the extent to which a product can be used by specified users to achieve specified goals with effectiveness, efficiency, and satisfaction in a specified context of use.