Ability Bazaar guide
What is WCAG? A plain-language guide
The short answer
WCAG stands for Web Content Accessibility Guidelines. Published by the World Wide Web Consortium, it is a testable technical standard for making web content accessible to people with visual, auditory, physical, speech, cognitive, language, learning and neurological disabilities.
WCAG is organised around four principles: content must be perceivable, operable, understandable and robust. Success criteria are assigned Level A, AA or AAA. Most laws and procurement programs that name WCAG use Level A and AA, but the version they reference varies.
What do perceivable, operable, understandable and robust mean?
| Principle | Plain-language meaning | Example |
|---|---|---|
| Perceivable | People can obtain the information in a form they can use. | Text alternatives for images and captions for video. |
| Operable | People can navigate and control the interface. | Keyboard access, visible focus and enough time. |
| Understandable | Content and behavior are clear and predictable. | Useful labels, instructions and error recovery. |
| Robust | Content works with current and future user agents and assistive technologies. | Controls expose correct names, roles, states and values. |
Sources for this section: [1]
What do Level A, AA and AAA mean?
Level A contains foundational requirements. Level AA adds requirements that address major barriers and is the common legal or policy target. Level AAA contains additional criteria, but W3C does not recommend requiring AAA conformance as a general policy for entire sites because some content cannot satisfy every AAA criterion.
Conformance at a level includes all criteria at that level and the levels below it. A claim also has requirements about the full page, complete processes, accessibility-supported ways of using technology and non-interference.
Which WCAG version is current?
WCAG 2.2 became a W3C Recommendation on October 5, 2023 and adds nine success criteria to WCAG 2.1. W3C recommends using the latest version when developing or updating accessibility efforts.
A legal or contractual target may be older. The DOJ Title II web rule names WCAG 2.1 Level A and AA, while Revised Section 508 incorporates WCAG 2.0 Level A and AA. Test the named baseline and document any additional 2.2 coverage.
Does WCAG conformance guarantee a barrier-free experience?
No standard captures every disability, technology, context and user preference. WCAG conformance is a strong technical baseline, not a promise that every person will complete every task without difficulty.
W3C recommends involving users with disabilities because they can find usability issues that conformance evaluation alone misses. User evaluation should complement—not replace—standards-based testing.
Sources for this section: [6]
How should a team start using WCAG?
- Choose and record the WCAG version and conformance level required by law, contract and policy.
- Train designers, developers, content authors, testers and procurement staff for their roles.
- Build accessible components and content patterns before scaling production.
- Use automation during development, then manually evaluate representative pages and workflows.
- Include people with disabilities throughout design and testing.
- Track findings to remediation and retest before release.
Frequently asked questions
- What does WCAG stand for?
WCAG stands for Web Content Accessibility Guidelines, published by the World Wide Web Consortium.
- What are the four WCAG principles?
They are perceivable, operable, understandable and robust, often abbreviated POUR.
- What is the common conformance target?
Level A and AA is the most common target, but the required WCAG version depends on the applicable law, contract or policy.
- Is WCAG itself a law?
WCAG is a technical standard. A law, regulation, contract or organizational policy may incorporate a particular version and level.
Sources
- W3C, Web Content Accessibility Guidelines 2.2
- W3C WAI, WCAG 2 Overview
- W3C, Understanding Conformance
- ADA.gov, First Steps Toward Complying with the Title II Web Rule
- Section508.gov, IT Accessibility Laws and Policies
- W3C WAI, Involving Users in Evaluating Web Accessibility
Sources were checked on August 21, 2026. Regulations, standards and product documentation can change; follow the linked source for the latest version.