WCAG 2.0 Overview
The Web Content Accessibility Guidelines 2.0 — the foundation of modern web accessibility standards worldwide.
What is WCAG 2.0?
WCAG 2.0 was published by the W3C in December 2008. It defines how to make web content more accessible to people with disabilities, including visual, auditory, physical, speech, cognitive, and neurological disabilities.
WCAG 2.0 has three conformance levels: A (minimum), AA (standard — required by most laws), and AAA (enhanced). Most legal requirements reference WCAG 2.0 Level AA.
The Four Principles (POUR)
Perceivable
Information and UI components must be presentable to users in ways they can perceive.
All non-text content has a text alternative.
Structure conveyed through presentation is also available in text.
Color is not the only visual means of conveying information.
Text has a contrast ratio of at least 4.5:1.
Operable
UI components and navigation must be operable by all users.
All functionality is available from a keyboard.
A mechanism exists to bypass repeated blocks of content.
Focus order preserves meaning and operability.
Keyboard focus indicator is visible.
Understandable
Information and the operation of the UI must be understandable.
The default human language of each page can be programmatically determined.
Receiving focus does not initiate a change of context.
Input errors are identified and described to the user in text.
Labels or instructions are provided when content requires user input.
Robust
Content must be robust enough to be interpreted by a wide variety of user agents, including assistive technologies.
Elements have complete start/end tags, are nested correctly, and have unique IDs.
All UI components have accessible names, roles, and states.
ConformPilot & WCAG 2.0
ConformPilot tests against all WCAG 2.0 A and AA success criteria using axe-core and Pa11y. When generating a VPAT, you can select WCAG 2.0 as the standard to map your audit results to each criterion automatically.