WCAG Accessibility Guide

Complete guide to WCAG 2.2 — the accessibility standard for the modern web.

What Is WCAG?

WCAG (Web Content Accessibility Guidelines) is the W3C's standard for web accessibility. Version 2.2 is current and is legally required in many jurisdictions.

The Four Principles (POUR)

  • Perceivable — information must be presentable in ways all users can perceive (includes color contrast)
  • Operable — interface components must be operable (keyboard, timing, motion)
  • Understandable — information and UI must be understandable
  • Robust — content must work with assistive technologies

Color Contrast Requirements

Success Criterion 1.4.3 (AA) and 1.4.6 (AAA) define contrast requirements:

  • AA Normal: 4.5:1 for text under 18pt
  • AA Large: 3:1 for text 18pt+ or 14pt bold
  • AAA Normal: 7:1
  • AAA Large: 4.5:1

Non-Text Contrast (1.4.11)

UI components and essential icons must have at least 3:1 contrast against adjacent colors. This includes buttons, form fields, focus indicators.

How to Test

  1. Test with our contrast checker for every text/background pair
  2. Test keyboard navigation (no mouse)
  3. Test with a screen reader (NVDA or VoiceOver)
  4. Test with zoom at 200%
  5. Test with the color blindness simulator

Frequently Asked Questions

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