Accessibility

What is WCAG?

Last modified 3/5/2025

The Web Content Accessibility Guidelines (WCAG) are an internationally recognized set of recommendations for making web content more accessible to people with disabilities. Developed by the World Wide Web Consortium (W3C), these guidelines provide universal standards for creating websites, web apps, and digital content can be used by people with various disabilities. 

Currently, the Americans with Disabilities Act (ADA) in the United States, Section 508 of the Rehabilitation Act and the Illinois Information Technology Accessibility Act mandates accessibility for websites and digital services and point to WCAG for guidance and compliance.

ADA Title II Update

US Department of Justice issued new regulation on April 24, 2024, that significantly updated digital accessibility requirements for state and local governments.

Title II of the ADA requires state and local governments to provide services, programs, and activities that are accessible to people with disabilities. Title II applies to all services, programs, or activities of state and local governments, including public universities. This accessibility obligation includes services, programs, and activities that are offered online and through mobile apps. 

 The new Web Rule lists specific requirements about how to ensure that web content and mobile applications (apps) are accessible to people with disabilities. All state and local governments’ web content, including content provided by mobile apps, needs to meet the WCAG Version 2.1, Level A & AA by the compliance date (April 24, 2026) unless there is an exception that applies.

Who Benefits?

WCAG helps people with:

  • Visual impairments
  • Hearing disabilities
  • Motor limitations
  • Cognitive challenges
  • Neurological differences

Understanding POUR: The Foundational Principles of Accessibility

WCAG is built around four core principles that form the acronym POUR: Perceivable, Operable, Understandable and Robust.

Perceivable

People must be able to perceive the information and user interface components, regardless of their abilities.

  • Content must be presented in ways that can be perceived through different senses
  • Provide text alternatives for non-text content
  • Create content that can be presented in different ways without losing meaning
  • Make it easier for users to see and hear content

Operable

User interface components and navigation must be operable for all users.

  • Ensure all functionality is available from a keyboard
  • Give users enough time to read and use content
  • Do not design content that could cause seizures
  • Provide ways to help users navigate, find content, and determine where they are

Understandable

Information and the operation of the user interface must be comprehensible.

  • Make text readable and understandable
  • Ensure web pages appear and operate in predictable ways
  • Help users avoid and correct mistakes in form inputs

Robust

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

  • Maximize compatibility with current and future user tools
  • Ensure content can be interpreted by different browsers and assistive technologies

WCAG 2.1 A & AA Success Criteria: Key Requirements

Level A (Minimum Accessibility)

Level A criteria address the most basic accessibility barriers:

  1. Keyboard Accessibility
    • All functionality must be available using a keyboard
    • No keyboard traps that prevent users from navigating away from an element
  2. Text Alternatives
    • Provide text alternatives for non-text content (images, icons, buttons)
    • Ensure alternative text conveys the same purpose or information
  3. Time-Based Media
    • Provide alternatives for time-based media like video and audio
    • Include captions for pre-recorded audio content
    • Offer audio descriptions for video content
  4. Adaptable Content
    • Ensure content can be presented in different ways without losing information
    • Support different screen orientations and magnifications
  5. Distinguishable Elements
    • Ensure sufficient color contrast for text and interactive elements
    • Do not rely solely on color to convey information

Level AA (Enhanced Accessibility)

Level AA builds upon A requirements with more comprehensive accessibility:

  1. Enhanced Keyboard Support
    • Provide visible focus indicators
    • Ensure logical keyboard navigation order
    • Allow users to skip repetitive content
  2. Color and Contrast
    • Maintain a minimum color contrast ratio of 4.5:1 for normal text
    • 3:1 contrast for large text
    • Ensure color is not the only means of conveying information
  3. Text Resizing
    • Content must be readable and functional when text is resized up to 200%
    • No loss of content or functionality when zoomed
  4. Multiple Ways to Access Content
    • Provide multiple methods to find pages (search, site map, navigation)
    • Create consistent navigation across the website
  5. Error Identification and Correction
    • Clearly identify form input errors
    • Provide specific error messages and suggestions
    • Allow users to review and correct information before submission
  6. Consistent Navigation
    • Maintain consistent page layout and navigation
    • Use predictable mechanisms for identifying and correcting errors