Color Blindness Simulator
See how any color appears to people with color vision deficiency
#3B82F6rgb(59, 130, 246)#418EFArgb(65, 142, 250)#007DF4rgb(0, 125, 244)#009EB0rgb(0, 158, 176)#7B7B7Brgb(123, 123, 123)About Color Vision Deficiency
Approximately 8% of men and 0.5% of women worldwide have some form of color vision deficiency. Protanopia (red-blind) and deuteranopia (green-blind) are the most common types. This tool uses scientifically accurate color transformation matrices to simulate how colors appear to individuals with these conditions, helping designers create more accessible interfaces.
Color Blindness Simulator
See how any color appears to people with color vision deficiency
Features
- Simulate four color vision deficiencies: protanopia (no L-cones), deuteranopia (no M-cones), tritanopia (no S-cones), achromatopsia (greyscale)
- Uses scientifically-accurate Brettel / Vienot / Machado transformation matrices
- Proper sRGB gamma correction before applying the matrix (linear-light math)
- Real-time hex-color input with side-by-side comparison
- Useful for verifying UI color contrast for ~8% of male users (red-green color blindness) and ~0.5% of female users
How to use
- Pick a color using the color picker or enter a hex value.
- View the simulated appearance for each type of color vision deficiency.
- Compare the original color with all four simulations side by side.
- Copy the simulated hex values for use in your designs.
Tips & Best Practices
- Protanopia and deuteranopia are the most common (red-green color blindness). Tritanopia (blue-yellow) is rare.
- Achromatopsia is total color blindness — extremely rare (~1 in 30,000), but a useful "ground truth" for ensuring contrast works on luminance alone.
- WCAG contrast requirements (4.5:1 for normal text) work for color blindness too — sufficient contrast → readable for everyone.
- For UI elements that rely on color alone (red error / green success), add an icon or text label.
- For data visualisations, palettes like Viridis, Cividis, and ColorBrewer's color-blind-friendly sets are safe by design.
FAQ
How accurate are these simulations?
The simulations use the Machado, Oliveira, and Fernandes (2009) color transformation matrices, which are among the most scientifically accurate models available for simulating color vision deficiency.
What is the most common type of color blindness?
Deuteranopia (green-blind) and protanopia (red-blind) are the most common, affecting approximately 6% and 2% of males respectively. Tritanopia (blue-blind) is rare, and achromatopsia (total color blindness) is extremely rare.
How can I make my designs more accessible?
Avoid relying solely on color to convey information. Use patterns, labels, and sufficient contrast. Test your color palette with this simulator to ensure critical UI elements remain distinguishable.
Is my data safe and private?
All processing happens locally in your browser. No data is sent to any server.
Is this tool free to use?
Yes, this tool is completely free with no registration required.