Contrast Checker
Image & design · Done in 3 steps
- 1Enter two colours
- 2
- 3
About
Check WCAG 2.x colour contrast for text and UI. See AA/AAA pass or fail, a live preview, and the closest passing colour with one click.
How to use it
- 1Enter a text colour and a background colour.
- 2Read the contrast ratio and the AA/AAA results.
- 3Check the live preview at different text sizes.
- 4If it fails, apply one of the suggested passing colours.
- You give
- Two colours in HEX, RGB or HSL
- You get
- Contrast ratio, WCAG AA/AAA results for normal and large text, and suggested fixes
- Good to know
- Implements the WCAG 2.x relative-luminance formula (not the draft APCA method used in WCAG 3). Transparent colours aren't blended with what's underneath.
- Privacy
- Processed on your device. Nothing is uploaded, stored or logged.
- Last tested
- 2026-10-28
FAQ
What contrast ratio do I need?
WCAG AA requires 4.5:1 for normal text and 3:1 for large text (24px, or 18.66px bold) and UI components. AAA requires 7:1 and 4.5:1.
How are the suggestions chosen?
We keep your colour's hue and saturation and move only its lightness until it just passes, so the fix stays as close as possible to your brand colour.
Why is 4.49:1 shown as a fail?
WCAG thresholds are strict, so the ratio is rounded down — a colour pair either meets 4.5:1 or it doesn't.
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