What counts as large text?
Large text is at least 18 point (24 px) regular, or 14 point (about 18.66 px) bold. Large text needs a lower ratio because bigger letters are easier to read.
Color Contrast Checker
Check the contrast ratio between text and background colours against WCAG AA and AAA thresholds, with a live preview.
Runs in your browser — nothing is uploaded
About the Color Contrast Checker
Contrast is what makes text readable for people with low vision, colour blindness, or who are reading on a bright screen in sunlight. The WCAG guidelines set minimum ratios: 4.5 to 1 for normal text at level AA, and 3 to 1 for large text.
Enter the text and background colours in HEX, or use the pickers. The ratio is computed from relative luminance, and the pass or fail rows show the result for AA and AAA at each text size.
FAQ
Color Contrast Checker — frequently asked
What is the difference between AA and AAA?
AA is the level most accessibility laws reference, and AAA is stricter. AAA normal text needs 7 to 1, which can be hard to achieve with brand colours, so many sites target AA and use AAA where possible.
Does contrast apply to icons and buttons?
Yes. Non-text elements such as icons, form borders and focus indicators need at least 3 to 1 against adjacent colours under WCAG 2.1 and 2.2, so check them too.
Why is the ratio not simply based on brightness?
The WCAG formula uses relative luminance, which weights green more than red and red more than blue, to match human vision. It is a better predictor of readability than a simple brightness average.
Does placeholder text need the same contrast?
Yes. Placeholder text is still text, and light grey placeholders on white fields are a common failure. Use a colour that passes AA on the field background.
Is my colour data stored?
No. The check runs in your browser and nothing is saved.
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