Color Contrast Checker
Calculates the WCAG contrast ratio between a text and background color and checks it against AA and AAA accessibility thresholds, with a live text preview.
The quick brown fox jumps over the lazy dog
Sample body text at normal size for contrast preview.
Contrast ratio: 17.40 : 1
| Level | Result |
|---|---|
| AA — normal text | Pass |
| AA — large text | Pass |
| AAA — normal text | Pass |
| AAA — large text | Pass |
Color Contrast Checker — Free Online Tool
Calculates the WCAG contrast ratio between a text and background color and checks it against AA and AAA accessibility thresholds, with a live text preview.
How to use the Color Contrast Checker
- Open the tool above — it runs entirely in your browser, so your input never leaves this page.
- Paste or type your input into the field, then press the relevant button (e.g. Encode / Decode, Generate, or Convert).
- Copy the result from the output area with the copy button orCtrl/Cmd + C.
- No signup, no upload, and no tracking — repeat as often as you need.
Frequently asked questions
Is the Color Contrast Checker free to use?
Yes. The Color Contrast Checker is completely free, with no signup, no ads inside the tool, and no hidden limits.
Does the Color Contrast Checker upload my data?
No. The Color Contrast Checker processes everything locally in your browser. Your input is never sent to a server, so it stays private even on shared devices.
Does the Color Contrast Checker work offline?
After the page loads, the Color Contrast Checker runs entirely in your browser, so it keeps working without a network connection.
Free & private — why use this Color Contrast Checker
The Color Contrast Checker runs 100% client-side in your browser. Your data is never uploaded to a server, no account is required, and the tool is completely free. It works offline once the page has loaded and is part of a growing collection of privacy-first developer utilities.