WCAG Level AA Accessibility Checklist

WCAG Level AA: The Standard Conformance Target

WCAG Level AA is the conformance level required by most accessibility laws and regulations worldwide, including the ADA (US), EN 301 549 (EU), and the Accessibility Regulations (UK). It includes all Level A criteria plus additional requirements.

Key Level AA Criteria

Level AA adds critical requirements beyond Level A:

• Color contrast — 4.5:1 ratio for normal text, 3:1 for large text (1.4.3)
• Resize text — Content usable at 200% zoom without loss (1.4.4)
• Reflow — No horizontal scrolling at 320px viewport width (1.4.10)
• Focus visible — Keyboard focus indicator always visible (2.4.7)
• Error suggestion — Error messages include correction suggestions (3.3.3)
• Status messages — Dynamic messages use ARIA live regions (4.1.3)

Legal Requirements

Most accessibility legislation targets Level AA conformance:

Regulation	Jurisdiction	Level Required
ADA Title III	United States	AA
Section 508	US Government	AA
EN 301 549	European Union	AA
AODA	Ontario, Canada	AA

Audit Strategy

For Level AA, audit all Level A criteria first, then add Level AA-specific criteria. Key testing areas include:

1. Color contrast across all text and UI components
2. Responsive behavior at 200% zoom and 320px width
3. Focus indicators on all interactive elements
4. Error handling in all forms with suggested corrections
5. Consistent navigation across all pages

Tools for Level AA Testing

Combine this manual checklist with automated tools:

• Color contrast: Use the Accessibility Color Checker tool
• HTML validation: W3C Markup Validator
• Automated scanning: axe DevTools, Lighthouse
• Screen reader testing: VoiceOver (macOS), NVDA (Windows)