APCA Contrast Calculator
Measure perceptual contrast with APCA 0.1.9 and compare it with classic WCAG 2.1 ratios.
About this tool
Measure Advanced Perceptual Contrast (APCA) for text and backgrounds, see typography-aware guidance, and compare WCAG 2.1 contrast. APCA Contrast Calculator runs in the browser on DevTools. There is no signup, and your input stays on this device unless the tool explicitly performs a live network lookup.
What this tool does not do
- APCA Contrast Calculator is a free in-browser utility, not a hosted API. It does not keep server-side history and is not a substitute for production verification in your own stack.
How do I use this tool?
How do I use APCA Contrast Calculator?
Open APCA Contrast Calculator, enter or paste your input, and copy the result. The page works without an account.
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