WCAG 2.1 Level AA

The Web Content Accessibility Guidelines (WCAG) 2.1 Level AA are a set of internationally recognized standards developed by the World Wide Web Consortium (W3C) to ensure that digital content is accessible to all users, including those with disabilities. These guidelines provide a comprehensive framework for making web content more accessible and user-friendly. The ADA Title II regulatory rule, published to the Federal Register in April 2024, establishes WCAG 2.1 Level AA as the technical standard for accessibility compliance.

Key Principles of WCAG 2.1

The WCAG 2.1 guidelines are organized around four core principles, known as POUR:

  • Perceivable: Information and user interface components must be presented in ways that users can perceive. This includes providing text alternatives for non-text content, creating content that can be presented in different ways (e.g., simpler layout) without losing information, and making it easier for users to see and hear content.
  • Operable: User interface components and navigation must be operable. This means making all functionality available from a keyboard, giving users enough time to read and use content, and helping users navigate and find content.
  • Understandable: Information and the operation of the user interface must be understandable. This involves making text readable and understandable, ensuring web pages appear and operate in predictable ways, and helping users avoid and correct mistakes.
  • Robust: Content must be robust enough to be interpreted reliably by a wide variety of user agents, including assistive technologies. This means ensuring compatibility with current and future user tools.

Overview of Success Criteria

Tab/Accordion Items

Information and user interface components must be presented in ways that users can perceive. Key success criteria include:

  • Text Alternatives: Provide text alternatives for non-text content, such as images and multimedia.
  • Time-Based Media: Offer alternatives for time-based media, including captions for videos and transcripts for audio.
  • Adaptable: Create content that can be presented in different ways without losing information or structure.
  • Distinguishable: Make it easier for users to see and hear content, including using sufficient contrast and allowing users to resize text.

User interface components and navigation must be operable. Key success criteria include:

  • Keyboard Accessible: Ensure all functionality is available from a keyboard.
  • Enough Time: Provide users with enough time to read and use content, including options to pause or extend time limits.
  • Seizures and Physical Reactions: Avoid content that can cause seizures, such as flashing elements.
  • Navigable: Help users navigate, find content, and determine where they are, including providing clear headings and consistent navigation.
  • Input Modalities: Make it easier for users to operate functionality through various inputs beyond the keyboard, such as touch or voice.

Information and the operation of the user interface must be understandable. Key success criteria include:

  • Readable: Make text content readable and understandable, using clear language and expandable abbreviations.
  • Predictable: Ensure web pages appear and operate in predictable ways, maintaining consistency across the site.
  • Input Assistance: Help users avoid and correct mistakes, providing error identification, suggestions, and prevention mechanisms.

Content must be robust enough to be interpreted reliably by a wide variety of user agents, including assistive technologies. Key success criteria include:

  • Compatibility: Ensure compatibility with current and future user agents, including using well-formed HTML and ensuring all elements have start and end tags.
  • Accessibility Supported: Use technologies that support accessibility and are compatible with assistive technologies.