What’s the difference between AA and AAA?

AA requires 4.5:1 contrast for normal text and 3:1 for large text—this is the legal baseline for most accessibility standards. AAA requires 7:1 and 4.5:1 respectively. AAA is harder to hit but recommended for body text on content-heavy sites.

Does this account for color blindness?

No. Contrast ratio measures luminance difference, which helps all users, but it doesn’t evaluate distinguishability for specific color vision deficiencies. Use a color blindness simulator alongside this tool for full coverage.

Color Accessibility Checker

About Color Accessibility Checker

Tests foreground/background color pairs against WCAG 2.1 contrast ratio requirements. Reports pass/fail for AA and AAA compliance at both normal and large text sizes. Includes a palette testing panel with common color sets and a suggestion engine that generates compliant color variations by adjusting lightness in 10% increments.

Calculates contrast ratio using the W3C relative luminance formula with sRGB gamma correction
Reports WCAG AA (4.5:1 normal, 3:1 large) and AAA (7:1 normal, 4.5:1 large) pass/fail
Large text threshold: 18px+ or 14px+ bold, matching WCAG definitions
Live preview renders sample text with your exact color combination, font size, and weight
Color suggestion engine generates 20 lighter/darker variations and filters for AA compliance
Save up to 10 color pair tests for side-by-side comparison; export full report as JSON

Frequently Asked Questions

What’s the difference between AA and AAA?: AA requires 4.5:1 contrast for normal text and 3:1 for large text—this is the legal baseline for most accessibility standards. AAA requires 7:1 and 4.5:1 respectively. AAA is harder to hit but recommended for body text on content-heavy sites.
Does this account for color blindness?: No. Contrast ratio measures luminance difference, which helps all users, but it doesn’t evaluate distinguishability for specific color vision deficiencies. Use a color blindness simulator alongside this tool for full coverage.

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