Color Blindness Simulator
See how any color or image URL looks to someone with protanopia (red blind), deuteranopia (green blind), tritanopia (blue blind), or achromatopsia (full monochrome). Uses CSS filter matrices to simulate each condition. Useful for testing contrast and accessibility compliance before shipping.
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Color Blindness Simulator: questions
How accurate is the simulation?
The SVG color-matrix values are established approximations based on published chromatic adaptation matrices (Brettel, Viénot, Mollon). They are not 100% clinically exact but are widely used in accessibility tooling.
Does this replace a real accessibility audit?
No — it is a quick sanity check. For production accessibility work, use a dedicated tool or test with actual color-blind users.
What is the most common form of color blindness?
Deuteranopia (green-blind) and deuteranomaly together affect about 5–6% of men. Protanopia/anomaly affects about 2%. Tritanopia is rare, under 0.01%.
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