Color Blindness Simulator

What is Color Vision Deficiency?

Color vision deficiency (CVD), commonly called color blindness, affects approximately 8% of men and 0.5% of women worldwide. It occurs when one or more types of cone cells in the retina are absent or function differently, altering color perception.

Types of Color Blindness

• Protanopia / Protanomaly: Reduced or absent red light sensitivity (L-cone). Reds appear darker and shift toward green/brown. Combined prevalence ~2% of males.
• Deuteranopia / Deuteranomaly: Reduced or absent green light sensitivity (M-cone). Greens and reds are confused. The most prevalent form — ~7% of males combined.
• Tritanopia / Tritanomaly: Reduced or absent blue light sensitivity (S-cone). Blues and yellows are confused. Very rare (~0.01%).
• Achromatopsia: Complete absence of color vision — the world appears in shades of gray. Extremely rare (~0.003%).

How the Simulation Works

This tool applies color transformation matrices based on the Brettel, Viénot, and Machado models for simulating color vision deficiencies. Each pixel's sRGB values are linearized, transformed through a 3×3 matrix that approximates how someone with a specific CVD perceives that color, then converted back to sRGB. Anomalous trichromacy (protanomaly, deuteranomaly, tritanomaly) uses an interpolation between normal vision and the full dichromacy matrix.

Design Tips for Accessibility

• Don't rely on color alone: Use patterns, labels, or icons alongside color coding.
• Test with this simulator: Check that key information remains distinguishable across all CVD types.
• Use high contrast: Ensure sufficient luminance contrast between adjacent colors.
• Choose CVD-friendly palettes: Blue-orange palettes work better than red-green ones.