Frontend tool

Colour Converter

Convert a colour between HEX, RGB and HSL, and check its contrast ratio against white and black for WCAG AA and AAA.

Colour

Pick

Formats

WCAG contrast

Contrast ratios follow WCAG 2.1 relative luminance. AA needs 4.5:1 for body text (3:1 for large text); AAA needs 7:1.

Runs in your browser

This tool is pure client-side JavaScript. Nothing you enter is sent to this server or anywhere else — you can verify it in your browser’s network tab.

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