WCAG accessibility contrast checker for text readability
Sample Text Preview
The quick brown fox jumps over the lazy dog.
| Level | Normal Text | Large Text | UI Components |
|---|---|---|---|
| AA | 4.5:1 | 3:1 | 3:1 |
| AAA | 7:1 | 4.5:1 | - |
Color contrast is essential for web accessibility. Users with visual impairments, color blindness, or low vision need sufficient contrast between text and background to read content. WCAG (Web Content Accessibility Guidelines) sets specific contrast ratios to ensure content is accessible to everyone.
Our tool calculates contrast ratios according to WCAG 2.1 standards and instantly tells you if your color combinations pass AA or AAA requirements for normal text, large text, and UI components.
For normal text, 4.5:1 is the minimum for WCAG AA compliance. 7:1 is required for AAA. Large text (18pt+ or 14pt+ bold) requires 3:1 for AA and 4.5:1 for AAA.
It uses the relative luminance of both colors: (L1 + 0.05) / (L2 + 0.05), where L1 is the lighter color and L2 is the darker color. Luminance is calculated from RGB values.
Yes! Google considers accessibility in its ranking algorithms. Accessible websites often rank higher and provide better user experience, reducing bounce rates.