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A11yCheck

WCAG contrast & accessibility checker 100% offline

1 · Pick your two colours

Quick pairs:

2 · Live preview

Colour-vision simulation:
Designing for everyone
Body copy is where contrast failures actually hurt. This paragraph is set at 16 px, which counts as normal text under WCAG 2.2 — it needs a contrast ratio of at least 4.5:1 to pass Level AA, and 7:1 for AAA.
Small print, captions and placeholder text still need the same 4.5:1 — there is no exemption for de-emphasised text, only for text that is genuinely disabled.
Read the documentation →
Buttons and links in the preview inherit your two colours so you can see the real thing, not just a number. Under WCAG 2.2, text at 18.66 px bold or 24 px regular counts as large text (3:1 for AA).

3 · Fix suggestions

4 · Check a whole palette

Every cell is the contrast ratio between that row and column as foreground-on-background. Green ≥ 4.5:1 (AA normal text), amber ≥ 3:1 (AA large text / non-text UI), red below both.
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