Web Content Accessibility Guidelines (WCAG) Overview
Web Content Accessibility Guidelines (WCAG) is developed through the W3C process in cooperation with individuals and organizations around the world, with a goal of providing a single shared standard for web content accessibility that meets the needs of individuals, organizations, and governments internationally.
The WCAG documents explain how to make web content more accessible to people with disabilities. Web “content” generally refers to the information in a web page or web application, including:
- natural information such as text, images, and sounds
- code or markup that defines structure, presentation, etc.
WCAG is primarily intended for:
- Web content developers (page authors, site designers, etc.)
- Web authoring tool developers
- Web accessibility evaluation tool developers
- Others who want or need a standard for web accessibility, including for mobile accessibility
Related resources are intended to meet the needs of many different people, including policy makers, managers, researchers, and others.
WCAG is a technical standard, not an introduction to accessibility. For introductory material, see Where should I start? in the FAQ.
WCAG 2.0 is a stable, referenceable technical standard. It has 12 guidelines that are organized under 4 principles: perceivable, operable, understandable, and robust. For each guideline, there are testable success criteria, which are at three levels: A, AA, and AAA.
For a short summary of the WCAG 2.0 guidelines, see WCAG 2.0 at a Glance.
To learn about web accessibility principles and guidelines, see Accessibility Principles.
The WCAG 2.0 supporting technical materials include:
- How to Meet WCAG 2.0: A customizable quick reference to Web Content Accessibility Guidelines 2.0 requirements (success criteria) and techniques is essentially the WCAG 2.0 checklist. Most people use this quick references as the main resource for working with WCAG.
- Techniques for WCAG 2.0 gives you specific details on how to develop accessible Web content, such as HTML code examples. The techniques are “informative”, that is, you do not have to use them. The basis for determining conformance to WCAG 2.0 is the success criteria from the WCAG 2.0 standard, not the techniques. Read more in Techniques in the FAQ.
- Understanding WCAG 2.0 has additional guidance on learning and implementing WCAG 2.0 for people who want to understand the guidelines and success criteria more thoroughly.
For more details on how these document are related and how they are linked, see The WCAG 2.0 Documents.
Technical document format
The WCAG, Techniques, and Understanding documents follow the W3C format for technical reports, which has several sections at the beginning, including links to different versions, editors, abstract, and status.