Free color contrast checker with APCA + WCAG dual engine — check any two colors against AA/AAA standards and WCAG 3.0-ready APCA scores. Paste a URL and get a full-page contrast audit with violation highlights. 15+ specialized tools: gradient, button, link, heading, form input, icon, color blindness simulator, palette generator, and more. Chrome extension + Figma plugin for your workflow. 100% browser-side — no sign-up, no data collection, no limits.