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Editors Draft: $Date: 2013-02-26 19:40:09 $
Status: This document is an in-progress or outdated draft. The published version is at: www.w3.org/WAI/eval/conformance
Please send comments to wai-eo-editors@w3.org (a publicly archived list).

WCAG-EM Overview:
Website Accessibility Conformance Evaluation Methodology

Page Contents


Website Accessibility Conformance Evaluation Methodology (WCAG-EM) is an approach for determining how well a website conforms to Web Content Accessibility Guidelines (WCAG) 2.0.

If you want to get a general sense of how a web page addresses a few accessibility issues, see Preliminary Review of Websites for Accessibility. It is usually best to do preliminary checks before applying WCAG-EM, and to address potential accessibility barriers before investing in a more thorough review such as WCAG-EM.

WCAG-EM is a supporting resource for the WCAG 2.0 standard; it does not define additional WCAG 2.0 requirements. It is currently in Working Draft stage, and is expected to be published as a W3C Working Group Note in 2013.


WCAG-EM applies to all websites, including web applications and mobile websites. It covers different situations, including self-assessment and third-party evaluation. It is independent of particular evaluation tools, web browsers, or assistive technologies.

WCAG-EM is primarily for evaluating conformance of existing websites. However, accessibility should not be left until the evaluation stage; it should be integrated from the beginning and throughout the project lifecycle — in planning, design, and development.

Other aspects of evaluation are addressed in related pages of the Evaluating Web Accessibility resource suite. For example, guidance to help you better understand real-world accessibility issues and evaluate effective accessibility solutions is in Involving Users in Evaluating Web Accessibility.

Who WCAG-EM is for

WCAG-EM is for anyone who wants a common procedure for auditing websites. It is for direct use by internal evaluators, external auditors, benchmarkers, and researchers. Additionally, WCAG-EM can be referred to by managers, procurers, policy makers, regulators, and others.

Applying WCAG-EM successfully requires knowledge of WCAG 2.0, accessible web design, assistive technologies, and how people with different disabilities use the Web (as described in the WCAG-EM Required Expertise technical report section).

What is in WCAG-EM

WCAG-EM provides guidance on using the methodology and considerations for specific situations. The conformance evaluation procedure is detailed under 5 main steps:

  1. Define the scope of the evaluation - defining what is included in the evaluation; the goal of the evaluation; and the WCAG conformance level (A, AA, AAA).
  2. Explore the website - identifying key web pages; key functionality; types of web content, designs, functionality, etc.; required web technologies.
  3. Select a representative sample - guidance on structured and randomly selected web pages when it is not feasible to evaluate every web page on a website.
  4. Evaluate the selected sample - determining successes and failures in meeting WCAG 2.0; accessibility support for website features; and recording evaluation steps.
  5. Report the evaluation findings - aggregating and reporting evaluation findings; making evaluation statements; and calculating overall scores.

Technical document format

WCAG-EM follows the W3C format for technical specifications which includes several sections at the beginning: links to different versions, editors, copyright, abstract, and status with the link to errata and the email address for comments. There is a link at the top to the Table of Contents.

Who develops WCAG-EM

WCAG-EM is developed by the WCAG 2.0 Evaluation Methodology Task Force (Eval TF), which is a joint task force of the Web Content Accessibility Guidelines Working Group (WCAG WG) and Evaluation and Repair Tools Working Group (ERT WG). The Working Groups are part of the World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI).

Formal periods for public review of WCAG-EM are described in How WAI Develops Accessibility Guidelines through the W3C Process: Milestones and Opportunities to Contribute.

Opportunities for contributing to WCAG-EM and other WAI work are introduced in Participating in WAI.