a small accessibility tool

Contrast Checker

Pick a foreground and a background color, and the page will tell you whether the combination meets the WCAG 2.2 contrast thresholds. The math follows the spec exactly, using the same relative-luminance formula that Lighthouse and axe use.

Foreground Background

The quick brown fox jumps over the lazy dog.

The quick brown fox jumps over the lazy dog.

The quick brown fox jumps over the lazy dog.

Small print also has to read at this contrast level.

Sample button

· : 1

· AA Normal text · 4.5
· AA Large text · 3.0
· AAA Normal text · 7.0
· AAA Large text · 4.5
· UI Components · 3.0

“Large” means 18pt regular (≈24px) or 14pt bold (≈18.66px). The UI tile covers icons, form borders, and chart elements per WCAG 2.2 SC 1.4.11.