Color Contrast Checker

Measure WCAG contrast between two hex colors and see AA / AAA.

Foreground

Background

Sample text

Calculated Result

17.74 : 1

AAA

Formula: (L1 + 0.05) / (L2 + 0.05) · WCAG 2.x relative luminance

About this calculator

Pick foreground and background. Body text needs 4.5:1 for AA. Large text can pass at 3:1. AAA is 7:1.

Formula(L1 + 0.05) / (L2 + 0.05) WCAG relative luminance

sRGB → linear, L = 0.2126R + 0.7152G + 0.0722B, ratio (L1+0.05)/(L2+0.05).

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