Color · Accessibility

Contrast checker.

Pick a text color and a background color and get the exact WCAG contrast ratio, with pass/fail against AA and AAA for normal text, large text, and UI components.

Colors

Result

Normal text sample (15px) — AaBbCc

Large text sample (24px)

21.00:1

How it works

Formula: WCAG relative luminance is computed for each color, then the ratio is (L1 + 0.05) / (L2 + 0.05) with the lighter color as L1.
Normal text needs 4.5:1 for AA and 7:1 for AAA.
Large text (≥24px, or ≥18.7px bold) needs 3:1 for AA and 4.5:1 for AAA.
UI components & graphics (buttons, icons, form borders — WCAG 2.1 SC 1.4.11) need 3:1.

Free vs Premium

This tool is fully free with no limit — contrast math doesn't get more accurate with a subscription, so there's no Premium tier here.