Web Content Accessibility Guidelines
WCAG 2.0 61 success criteria · W3C Recommendation
WCAG 2.0 turned the guidelines into testable success criteria: 61 of them, under four principles and 12 guidelines. W3C published it on 11 December 2008. It became ISO/IEC 40500:2012, which ISO withdrew in September 2025 when WCAG 2.2 took the same number.
- Level A
- 25
- Level AA
- 13
- Level AAA
- 23
- Published
- 11 December 2008
The structure
Four principles, twelve guidelines
Every success criterion sits under a guideline, and every guideline under one of four principles: content must be perceivable, operable, understandable and robust.
1 Perceivable
Information and interface must be presentable in ways people can perceive.
- 1.1 Text Alternatives
- 1.2 Time-based Media
- 1.3 Adaptable
- 1.4 Distinguishable
2 Operable
Interface components and navigation must be operable.
- 2.1 Keyboard Accessible
- 2.2 Enough Time
- 2.3 Seizures and Physical Reactions
- 2.4 Navigable
3 Understandable
Information and the operation of the interface must be understandable.
- 3.1 Readable
- 3.2 Predictable
- 3.3 Input Assistance
4 Robust
Content must be robust enough to work with current and future user agents, including assistive technology.
- 4.1 Compatible
Every criterion
All 61 success criteria in WCAG 2.0
Search, or filter by level and principle. Each one links to its page with a live demo and code examples.
Showing 61 of 61
1. Perceivable
Information and interface must be presentable in ways people can perceive.
22 criteria
A 9AA 5AAA 8
Text Alternatives
1 criterion
Time-based Media
9 criteria
- 1.2.1Level A Audio-only and Video-only (Prerecorded)
- 1.2.2Level A Captions (Prerecorded)
- 1.2.3Level A Audio Description or Media Alternative (Prerecorded)
- 1.2.4Level AA Captions (Live)
- 1.2.5Level AA Audio Description (Prerecorded)
- 1.2.6Level AAA Sign Language (Prerecorded)
- 1.2.7Level AAA Extended Audio Description (Prerecorded)
- 1.2.8Level AAA Media Alternative (Prerecorded)
- 1.2.9Level AAA Audio-only (Live)
Adaptable
3 criteria
Distinguishable
9 criteria
2. Operable
Interface components and navigation must be operable.
20 criteria
A 9AA 3AAA 8
Keyboard Accessible
3 criteria
Enough Time
5 criteria
Seizures and Physical Reactions
2 criteria
Navigable
10 criteria
- 2.4.1Level A Bypass Blocks
- 2.4.2Level A Page Titled
- 2.4.3Level A Focus Order
- 2.4.4Level A Link Purpose (In Context)
- 2.4.5Level AA Multiple Ways
- 2.4.6Level AA Headings and Labels
- 2.4.7Level AA Focus Visible
- 2.4.8Level AAA Location
- 2.4.9Level AAA Link Purpose (Link Only)
- 2.4.10Level AAA Section Headings
3. Understandable
Information and the operation of the interface must be understandable.
17 criteria
A 5AA 5AAA 7
Readable
6 criteria
Predictable
5 criteria
4. Robust
Content must be robust enough to work with current and future user agents, including assistive technology.
2 criteria
A 2AA 0AAA 0
Compatible
2 criteria
- In WCAG 2.0
- New in 2.1
- New in 2.2
- Removed in 2.2
| Guideline | Level A25 | Level AA13 | Level AAA23 |
|---|---|---|---|
| 1 Perceivable | |||
| 1.1 Text Alternatives | — | — | — |
| 1.2 Time-based Media |
| — |
|
| 1.3 Adaptable | — | — | — |
| 1.4 Distinguishable | — | — |
|
| 2 Operable | |||
| 2.1 Keyboard Accessible | — | — | — |
| 2.2 Enough Time | — | — | — |
| 2.3 Seizures and Physical Reactions | — | — | — |
| 2.4 Navigable | — | — | — |
| 3 Understandable | |||
| 3.1 Readable | — | — | — |
| 3.2 Predictable | — | — | — |
| 3.3 Input Assistance | — | — | — |
| 4 Robust | |||
| 4.1 Compatible | — | — | — |
No criterion matches these filters.
Conformance
What conformance means
A page conforms at a level when it meets every criterion at that level and below, and these five requirements hold.
Level
Every criterion at the chosen level and the levels below it is met, or a conforming alternate version is offered.
Full pages
Conformance covers whole pages: a page cannot conform while leaving a part of it out.
Complete processes
When a page is one step of a process, such as a checkout, every step conforms.
Accessibility-supported ways only
The ways content meets the criteria must work with assistive technology and browsers people use.
Non-interference
Anything that is not accessibility-supported must not block the rest of the page; 1.4.2, 2.1.2, 2.2.2 and 2.3.1 apply to everything on it.
Editions
Editions and standards
Content that meets WCAG 2.1 or 2.2 also meets 2.0, apart from 4.1.1 Parsing, which 2.2 removed.
Read WCAG 2.0 at W3C- Recommendation: 11 December 2008. W3C never republished it; its corrections, including the 2023 note on 4.1.1, are on the errata page.
- ISO/IEC 40500:2012, published 12 October 2012 and withdrawn 24 September 2025.