Color Blindness Simulator
Preview how a color palette looks to people with color vision deficiencies.
See how your colors look to people with color vision deficiencies. Paste a palette (one color per line, or comma-separated) in hex, rgb(), hsl(), or by name. The dichromat rows use the Machado 2009 model, the same one Chrome DevTools uses. Around 1 in 12 men has some form of color blindness, so it's worth checking that a palette still reads clearly.
Normal vision
~92% of men, ~99.5% of womenFull color vision, shown for reference.
Deuteranopia
~6% of menGreen-blind - the most common red-green deficiency.
Protanopia
~2% of menRed-blind - reds look darker and shift toward green.
Tritanopia
very rare (<0.01%)Blue-blind - blues and yellows are hard to tell apart.
Achromatopsia
extremely rareTotal color blindness - everything is shades of gray.
About Color Blindness Simulator
Paste a palette and see it the way someone with a color vision deficiency would. It simulates the three dichromacies - deuteranopia, protanopia, and tritanopia - plus total color blindness (achromatopsia), so you can tell whether your colors stay distinguishable. The red-green simulations use the Machado 2009 model, the same one built into Chrome DevTools. Around 1 in 12 men and 1 in 200 women has some degree of color blindness, so a palette that relies on red-vs-green alone can fall apart for a real slice of your audience. Everything runs in your browser.
Why this matters
Color is a common way to signal meaning - a green 'success' next to a red 'error', a status dot, a chart legend. But roughly 8% of men and 0.5% of women see color differently, and red-green deficiency is by far the most common kind. If two colors that carry different meanings look the same to them, the information is gone. Checking a palette here takes seconds and tells you whether you need a second cue like a label, icon, or shape.
How the simulation works
Each color is converted from sRGB to linear light, transformed by the relevant color-blindness matrix, then converted back. The deuteranopia, protanopia, and tritanopia rows use the Machado, Oliveira & Fernandes (2009) matrices at full severity - the model Chrome DevTools uses for its vision-deficiency emulation. Achromatopsia is a relative-luminance grayscale. These simulate the dichromat (full) forms, which are the strongest case. Milder anomalous forms (deuteranomaly and so on) sit between normal vision and these.
Reading the result
- Compare each row against the normal-vision row
- If colors that mean different things collapse to near-identical swatches, they're a problem
- Watch red-green pairs in deuteranopia and protanopia especially
- Don't rely on color alone - add text, icons, or patterns
- Check both text and background combinations, not just accent colors