Color Blindness Simulator
Simulate eight types of color blindness on any image or hex palette and compare it with the original.
Deuteranopia: the green cones are missing — the classic red/green colour blindness. Affects roughly 1% of men.
Palette check
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#E63946looks like#988940 -
#2A9D8Flooks like#858890 -
#457B9Dlooks like#5F719C -
#F4A261looks like#CEBC61
No confusable pairs: all 4 colours stay distinguishable with deuteranopia.
Image check
Drag & drop an image here, or click to browse
No uploads. Your files stay on your device.
How it works
Around 1 in 12 men and 1 in 200 women have some form of colour vision deficiency, so a
palette that reads clearly to you can be unreadable to them. Pick a type of colour blindness
and this tool shows you exactly what it does to your colours: paste hex or
rgb() values to check a palette, or drop in a screenshot, chart or logo to see
the whole image simulated side by side with the original.
The simulation uses the Machado, Oliveira & Fernandes (2009) colour vision deficiency matrices — the same model used by Chrome DevTools — applied in linear RGB, with achromatopsia rendered as true luminance grey. Anomalous types (protanomaly, deuteranomaly, tritanomaly) use a moderate severity of 0.6, so they sit between normal vision and the full dichromatic version. The palette check also flags pairs of colours that stay far apart for you but collapse into nearly the same colour under the selected deficiency — those are the pairs to avoid using as your only signal in a chart or a status badge. Everything is computed in your browser with the Canvas API: no image or colour ever leaves your device.
Frequently asked questions
What does color blindness look like?
It depends on the type. With deuteranopia and protanopia (red-green color blindness) reds, greens, oranges and browns collapse toward the same muddy yellow-olive, so a red warning next to a green success badge can look identical. With tritanopia, blues turn greenish and yellows turn pink. With achromatopsia there is no color at all, only shades of grey. Drop an image or paste your hex codes into this simulator and pick a type to see the exact result side by side with the original.
How do I check if my design is color blind friendly?
Paste every color in your palette into the palette check and step through the eight deficiency types. This tool flags any two colors that are easy to tell apart with normal vision but become nearly identical when simulated — those are the pairs you must not rely on alone. Then upload a screenshot of the real interface or chart to confirm. The fix is usually to add a second cue: labels, icons, patterns, or a clear difference in lightness rather than only in hue.
What is the most common type of color blindness?
Deuteranomaly — weak green cones — is the most common form, affecting roughly 5% of men. Together with deuteranopia, protanomaly and protanopia it makes up almost all red-green color blindness, which affects about 1 in 12 men and 1 in 200 women. Blue-yellow types (tritanomaly and tritanopia) and full color blindness (achromatopsia) are rare, but this simulator includes all eight so you can check the complete range.