Color-Blindness Simulator + Corrector

Simulate and correct color-blindness (CVD) locally with a single fast SVG filter. Private — no data leaves your device.

See the web the way others do — then fix it so you can too. Color-Blindness Simulator + Corrector is a fast, 100% on-device tool for color vision. In one click it SIMULATES how any web page looks to someone with color-vision deficiency (CVD) — and, uniquely, it can CORRECT the page so confusable colors become easy to tell apart. FREE — Simulate 8 color-vision types • Protanopia, Protanomaly, Deuteranopia, Deuteranomaly, Tritanopia, Tritanomaly, Achromatopsia and Achromatomaly • Powered by the validated Machado-2009 color matrices for scientific accuracy • Applied instantly with a single SVG color-matrix filter — no lag, nothing rewritten on the page • Toggle on and off; every page fully reverts, every time • A live in-popup preview (swatch spectrum + Ishihara disc) lets you feel each mode before you ever touch a page PRO — Daltonize: correct, don't just simulate • The only extension that RECOLORS the live page so red-green and blue-yellow confusable pairs become distinguishable • Adjustable correction strength (0–100%), dialed to your own vision • Per-site profiles automatically re-apply your exact settings the moment a page loads Private by design • 100% on-device — every filter runs locally; your pages never leave your device • No account, no servers, no tracking, no telemetry, ever • Minimal permissions: broad site access is optional and opt-in, and you can revoke it any time Who it's for • Designers and developers checking that a UI stays readable for color-blind users • Anyone with color-vision deficiency who wants the web to be easier to read • Educators and accessibility professionals demonstrating how CVD changes perception No data collected. No sign-in. Just open the popup and click.