OpticQuiz — Colorblind Corrector

Correct colors on any web page for your type of color blindness, in real time. Published method, zero tracking.

OpticQuiz Colorblind Corrector re-colors any web page in real time so people with color vision deficiency (CVD) can tell apart colors that normally blur together. About 1 in 12 men are red-green colorblind. Maps, charts, wiring diagrams, dashboards, and red warning text often carry their meaning in exactly the colors that collapse for these viewers. This extension shifts those colors into ones you can distinguish. Click the toolbar icon and choose a mode: • Recommended — helps all types (pick this if you don't know your type) • Deuteranopia — green-weak, the most common • Protanopia — red-weak • Tritanopia — blue-yellow • Off — normal colors It corrects (daltonization); it does not just simulate. The correction runs entirely in your browser as an SVG color filter, using a published, open-access method (Machado 2009 simulation, scored with CIEDE2000 — DOI 10.5281/zenodo.21310578). Private by design: no tracking, no analytics, no accounts, and no data ever leaves your browser. Your chosen mode is stored only on your device. This is an aid, not a cure. It strongly improves color separation but will not resolve every case, and on pages that rely on fixed/sticky positioning the layout may shift while a mode is on — switch to Off to restore. Part of OpticQuiz, a color-accessibility platform: https://opticquiz.com Version history 1.3.0 — 2 Oct 2026 Corrected pages no longer cost you contrast. The correction now applies to page styles instead of filtering the whole screen. Three things change: photographs, video and canvas are never altered; pages built with fixed or sticky layouts no longer shift while a mode is on; and text is set to pure black or white against its corrected background, so it always stays readable — the previous version could reduce text contrast as a side effect of correcting color. Charts, backgrounds, borders and icons still get the full correction, which is where color-coded information actually lives. 1.2.0 — 4 Aug 2026 Added a strength control, and made it set itself. Correction used to be all-or-nothing per type, so someone with mild deuteranomaly — the most common color-vision deficiency there is — got a full dichromacy transform. Measured across 10 real palettes and 5 simulators, that was actively harmful at moderate severity. Strength now scales from 0 to 100%. If you've taken a vision test on opticquiz.com, the extension reads that result from your own device and sets your strength for you. No account, no diagnosis, no data leaves your browser. 1.1.0 — 4 Aug 2026 New deuteranopia and tritanopia matrices, derived against held-out simulators. Deuteranopia recovers noticeably more confusable color pairs; tritanopia does too, while halving the damage done to palettes that were already colorblind-safe. Protanopia deliberately stayed on the previous matrix — the new candidate passed the numeric checks but looked worse on real content, so it wasn't shipped. Protanopia is an open problem here, not a solved one. 1.0.2 — 3 Aug 2026 Per-size toolbar icons. The dotted eye mark averaged into an unreadable grey ring at 16px, which is exactly the size that lives in your toolbar all day. Also dropped the extension payload from 588 KB of icon to 13 KB. 1.0.1 — 28 Jul 2026 Removed the tabs permission and host permissions entirely. The popup now just saves your choice, and each page picks it up on its own. Smaller permission footprint, nothing lost. 1.0.0 — 27 Jul 2026 First release. Corrects colors on any page you visit — Recommended, Deuteranopia, Protanopia, Tritanopia, or Off. Your choice is remembered. No network requests, no tracking, no account.