Free Color Contrast Checker (WCAG)
Pick a text and background color and get the WCAG contrast ratio · with pass/fail for AA and AAA at normal and large text sizes.
Frequently asked
What ratio do I need to pass WCAG AA?
4.5:1 for normal text, 3:1 for large text (18pt+, or 14pt bold) and UI components. AAA raises text to 7:1. These come from WCAG 2.x and are the baseline most accessibility regulations reference.
Is contrast a legal requirement?
Increasingly yes · the European Accessibility Act (enforced since June 2025), ADA case law in the US, and public-sector mandates all reference WCAG. Low contrast is also the single most common automated accessibility failure on the web.
Related tools
- MIME Type Lookup · Search by file extension or MIME type · get the correct Content-Type for serving any file, with notes on the security-sensitive ones.
- HTTP Status Codes · Every HTTP status code, searchable · what each means, when to use it, and which ones have security implications worth knowing.
- Port Number Lookup · Search any port number or service · see what normally runs there and whether it belongs on the public internet.