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Color Contrast Checker

Check WCAG contrast ratio between two colors.

Almost before we knew it,

we had left the ground. — sample text

Contrast Ratio
17.06:1
AA · NormalPass
AA · LargePass
AAA · NormalPass
AAA · LargePass

WCAG Contrast, Explained

Web accessibility guidelines (WCAG) require sufficient contrast between text and its background so everyone can read it. The ratio ranges from 1:1 (identical) to 21:1 (black on white). The thresholds: AA needs 4.5:1 for normal text and 3:1 for large text (≥18.66px bold or ≥24px); AAA needs 7:1 and 4.5:1 respectively. Ratios use the official relative-luminance formula, computed locally in your browser.

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