WCAG Color Contrast Checker Online — Test HEX Colors
Check the WCAG contrast ratio between two HEX colors and test AA and AAA text thresholds locally.
About this tool
This contrast checker calculates relative luminance from two HEX colors and reports the ratio plus WCAG AA normal, AA large and AAA normal text results.
How to use
- Enter foreground and background HEX colors.
- Calculate the contrast ratio.
- Review pass or fail thresholds and test the real interface.
Features
- Calculates the WCAG contrast ratio.
- Reports AA and AAA text checks.
- Processes colors locally.
Common use cases
- Check text and background colors.
- Review design-system palettes.
- Improve accessibility before release.
Common issues and tips
- Automated contrast does not replace full accessibility testing.
- Large-text status depends on actual font size and weight.
Privacy
Color calculation runs locally.
Frequently asked questions
What ratio passes AA normal text?
A ratio of at least 4.5:1.
What passes AA large text?
A ratio of at least 3:1.
Does passing guarantee accessibility?
No. Also test states, typography, focus and usability.