The plain-English explainer

What is WCAG?

WCAG, the Web Content Accessibility Guidelines, is the international standard for digital accessibility. It is built on four principles and three conformance levels, and it is the benchmark that the EAA, the ADA and Section 508 all rely on. WCAG 2.2 is the current version; this page explains it plainly.

Reviewed by the EAA Navigator team

TL;DR

  • What: the W3C standard for digital accessibility, built on the POUR principles.
  • Levels: A, AA and AAA. Level AA is the target almost every law points to.
  • Versions: 2.0 (2008), 2.1 (2018) and 2.2 (a W3C Recommendation since October 2023).
  • Counts: WCAG 2.1 AA has 50 success criteria; WCAG 2.2 AA has 55, a net of five more.
  • 3.0: still an early draft, not a compliance target. Aim for 2.2 AA.
Get the WCAG checklistStart with the basics

The three levels

A

The most basic level. Necessary, but not the target.

AA

The legal and practical target. What the EAA, the ADA and Section 508 all aim at.

AAA

The highest bar. Not expected across a whole site.

Aim for Level AA across the board. W3C / WAI overview

What WCAG is, and where it comes from

WCAG stands for the Web Content Accessibility Guidelines. It is published by the World Wide Web Consortium (W3C), the body that sets the open standards of the web, through its Web Accessibility Initiative (WAI). WCAG is the international reference for making digital content usable by people with disabilities, and it is the standard that accessibility laws around the world point to. W3C / WAI

The guidelines have evolved in versions: WCAG 2.0 in 2008, WCAG 2.1 on 5 June 2018, and WCAG 2.2, which became a W3C Recommendation on 5 October 2023. Each version builds on the last, so meeting the newer version also meets the older one. WCAG 3.0 exists only as an early Working Draft and is not a compliance target. WCAG 2.2

The three conformance levels

Every WCAG success criterion is assigned a level. The levels are cumulative: to claim AA you must meet A and AA; to claim AAA you must meet all three.

  • Level A is the floor. Failing it tends to block users outright.
  • Level AA is the target almost every law adopts: EN 301 549, the DOJ Title II rule, Section 508 and most ADA case law.
  • Level AAA is the most demanding. The W3C itself does not recommend requiring AAA across a whole site, because not all content can meet it.

In short, aim for Level AA. That is what compliance means in practice.

The POUR principles, with examples

WCAG groups all of its success criteria under four principles, known by the initials POUR. Content must be perceivable, operable, understandable and robust.

Perceivable

Information must be available to the senses. For example: alt text for images, captions and transcripts for media, and a contrast ratio of at least 4.5:1 for normal text.

Operable

The interface must be usable by everyone. For example: full keyboard operation, a visible focus indicator, skip links, and no content that flashes more than three times a second.

Understandable

Content and controls must make sense. For example: readable language, consistent and predictable navigation, labelled form fields, and clear, specific error messages.

Robust

Content must work with a wide range of tools, now and in future. For example: valid markup, correct names, roles and values, and status messages that assistive technology can announce.

How many success criteria? 2.1 vs 2.2

WCAG turns the four principles into specific, testable success criteria. The count matters because it is how you scope an audit.

  • WCAG 2.1 Level AA: 50 success criteria.
  • WCAG 2.2 Level AA: 55 success criteria.

WCAG 2.2 added nine new success criteria across the levels and removed one (4.1.1 Parsing, now obsolete), giving a net of five more at each level. So it is not nine more at AA, it is five more, taking AA from 50 to 55. What's New in WCAG 2.2 (W3C)

The key new WCAG 2.2 AA criteria

These are the new Level AA criteria most teams need to act on. (Two more new ones, Consistent Help and Redundant Entry, are Level A.)

Focus Not Obscured (Minimum)

2.4.11 [AA]. When an element gets keyboard focus, it must not be entirely hidden behind sticky headers, cookie banners or other overlapping content.

Dragging Movements

2.5.7 [AA]. Anything that works by dragging (sliders, drag-and-drop) must also have a simple single-pointer alternative, such as tapping or clicking.

Target Size (Minimum)

2.5.8 [AA]. Interactive targets must be at least 24 by 24 CSS pixels, or have enough spacing, so they are easy to hit. Some exceptions apply.

Accessible Authentication (Minimum)

3.3.8 [AA]. Login must not force a cognitive test such as remembering a password or solving a puzzle, unless an alternative or a helper (like a password manager) is allowed.

Focus Appearance is AAA, not AA

Focus Appearance (2.4.13) is a new WCAG 2.2 criterion, but it sits at Level AAA, so it is not part of the AA target. Do not confuse it with Focus Not Obscured (Minimum), which is AA.

How WCAG maps into the law

WCAG is a voluntary standard on its own. It gets legal force because regulations and standards reference it.

  • EU, EN 301 549: the EU harmonised standard incorporates WCAG 2.1 AA in its Chapter 9. Meeting WCAG AA gives a presumption of conformity under both the EAA and the public-sector Web Accessibility Directive. EN 301 549
  • US, ADA & Title II: the DOJ Title II rule adopts WCAG 2.1 AA for state and local government, and ADA Title III case law uses WCAG AA as the de-facto benchmark. DOJ web rule
  • US, Section 508: the 2017 refresh incorporates WCAG 2.0 AA for federal ICT procurement. US Access Board

The practical upshot: build to WCAG 2.2 AA and you satisfy the WCAG 2.1 AA that the laws require, with headroom for the future. See how it fits each law on our EAA and ADA pages.

What about WCAG 3.0?

You may hear about WCAG 3.0. It is an ambitious rethink of how accessibility is measured, but it is still an early W3C Working Draft. It is years from being a finished standard and is not a compliance target. Plan around WCAG 2.2 AA; treat 3.0 as something to watch, not to act on yet.

Put it into practice

Ready to test your own site? Grab the WCAG 2.2 AA checklist, or follow the guides for specific fixes. The glossary explains any term you are not sure of.

By the numbers

WCAG in a few figures

4

Principles: Perceivable, Operable, Understandable, Robust (POUR).

3

Conformance levels: A, AA and AAA. Aim for AA.

55

Success criteria at WCAG 2.2 Level AA (50 at WCAG 2.1 AA).

24px

The minimum target size for interactive controls, new in 2.2 AA.

Counts per the W3C. What's New in WCAG 2.2

FAQ

People also ask

What is WCAG?
WCAG, the Web Content Accessibility Guidelines, is the international standard for digital accessibility, published by the World Wide Web Consortium (W3C). It is organised around four principles (Perceivable, Operable, Understandable, Robust) and turns them into testable success criteria at three conformance levels: A, AA and AAA.
What is the difference between WCAG A, AA and AAA?
A is the most basic level, AA is the practical and legal target almost every law points to, and AAA is the highest bar and is not expected across a whole site. When people talk about WCAG compliance they almost always mean Level AA.
What is the difference between WCAG 2.1 and 2.2?
WCAG 2.2 (a W3C Recommendation since 5 October 2023) builds on 2.1 (June 2018). It added nine new success criteria across the levels and removed one (4.1.1 Parsing), giving a net of five more criteria at each level. At Level AA, the count goes from 50 in 2.1 to 55 in 2.2.
What are the new WCAG 2.2 AA criteria?
The new Level AA criteria in 2.2 are Focus Not Obscured (Minimum), Dragging Movements, Target Size (Minimum) at 24 by 24 CSS pixels, and Accessible Authentication (Minimum). Focus Appearance is a new criterion too, but it is Level AAA, not AA. Consistent Help and Redundant Entry are new at Level A.
How does WCAG relate to the EAA, ADA and Section 508?
WCAG is the underlying standard the laws reference. In the EU, EN 301 549 incorporates WCAG 2.1 AA and is the harmonised standard for the EAA and the public-sector Web Accessibility Directive. In the US, the DOJ Title II rule adopts WCAG 2.1 AA, Section 508 references WCAG 2.0 AA, and ADA case law uses WCAG AA.
Is WCAG 3.0 the standard now?
No. WCAG 3.0 is an early W3C Working Draft, not a finished standard, and it is not a compliance target. WCAG 2.1 AA remains the legal benchmark, with WCAG 2.2 AA as current best practice. Do not plan compliance around WCAG 3.0 yet.
Which WCAG version should I aim for?
Target WCAG 2.2 Level AA. It includes everything in 2.1 AA (the level most laws require) plus the newer 2.2 criteria, so meeting 2.2 AA also satisfies 2.1 AA and sets you up well for the future.

This is guidance, not legal advice

This is guidance to help you understand WCAG, not legal advice. For decisions specific to your organisation, confirm with the official sources we link or a qualified adviser. We cannot guarantee compliance, and you should be wary of anyone who says they can.

Sources

  1. [1]Web Content Accessibility Guidelines (WCAG) 2.2 (W3C Recommendation)retrieved 9 Jun 2026
  2. [2]What's New in WCAG 2.2 (W3C)retrieved 9 Jun 2026
  3. [3]WCAG overview (W3C / Web Accessibility Initiative)retrieved 9 Jun 2026
  4. [4]EN 301 549 v3.2.1, the EU harmonised ICT accessibility standard (ETSI)retrieved 9 Jun 2026
  5. [5]Directive (EU) 2019/882 (European Accessibility Act), EUR-Lexretrieved 9 Jun 2026
  6. [6]US DOJ: ADA Title II web rule fact sheetretrieved 9 Jun 2026
  7. [7]US Access Board: Section 508 / ICT standardsretrieved 9 Jun 2026

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What is WCAG? WCAG 2.1 & 2.2 AA explained · EAA Navigator