See your colours through colour-blind eyes — instantly
Color Blindness Simulator
No L (red) cones. Reds appear dark; red-green confusion.
No M (green) cones. Most common; red-green confusion.
No S (blue) cones. Blue-yellow confusion; rarest form.
No colour perception at all (rod monochromacy). Greyscale only.
The Color Blindness Simulator lets designers and developers preview any colour as it appears to people with protanopia (red-blind), deuteranopia (green-blind), tritanopia (blue-blind), or achromatopsia (no colour perception). Enter any hex or RGB value and instantly see a side-by-side comparison — no install, no signup, completely free. Build more accessible, inclusive colour palettes today.
Both cause red-green colour confusion, but for different reasons. Protanopia means the eye has no functioning L (long-wavelength, red-sensitive) cones, making reds appear very dark. Deuteranopia means no M (medium-wavelength, green-sensitive) cones. Deuteranopia is roughly twice as common, affecting about 5% of males.
The simulator uses linearised sRGB colour matrices derived from the Brettel/Viénot cone-response models, which are the industry-standard approach used in professional accessibility tools. Colours are converted to linear light space before transformation and then gamma-corrected back, giving perceptually accurate results.
Approximately 8% of males and 0.5% of females have some form of colour vision deficiency. Red-green deficiencies (protanopia and deuteranopia together) account for the vast majority. Tritanopia is much rarer, affecting fewer than 1 in 10,000 people.
Never rely on colour as the only way to convey information — always pair it with icons, text labels, or patterns. Avoid problematic red/green combinations as the sole visual differentiator. Aim for WCAG contrast ratios of at least 4.5:1 for body text. Blue-orange colour pairings are generally safer for most types of colour blindness.