Color blindness simulator
Drop your palette in and see what survives for users with color vision deficiencies. The first color acts as background, the second as text, and every row shows the simulated contrast.
Load from the library
Click a palette to load its first four role colors
How the simulation works
The three dichromacy types are approximated with projection matrices in linear RGB space (the simplified Viénot / Brettel models common in color-vision research): convert to linear, collapse the dimension carried by the missing cone type, convert back to sRGB.
Achromatopsia keeps only the luminance channel, i.e. plain grayscale. Individual perception varies, so treat the results as directional rather than pixel-exact.
The sturdiest rules in practice: never encode state in red versus green alone (pair it with icons or text), and rely on lightness differences more than hue. A palette whose simulated contrast stays above 4.5:1 in all four rows is a very safe combination.