Color Blindness Simulator
Upload a photo or pick a sample to see how it looks to people with different types of color vision deficiency. Everything runs in your browser — your images are never uploaded.
Simulations use standard color-matrix approximations and depend on your screen. They illustrate color vision deficiency but are not a medical diagnosis.
What is color blindness?
Color blindness — more precisely, color vision deficiency (CVD) — is a reduced ability to tell certain colors apart. It affects roughly 1 in 12 men and 1 in 200 women. Most people with CVD don't see in greyscale; they simply confuse particular color pairs, most often reds and greens.
Types of color vision deficiency
- Red-green (most common): deuteranomaly and deuteranopia (green), protanomaly and protanopia (red).
- Blue-yellow (rarer): tritanomaly and tritanopia affect the blue cones.
- Complete (very rare): achromatopsia, where little or no color is perceived at all.
The -anomaly forms are milder (a cone type works weakly); the -anopia forms are stronger (a cone type is missing). The grid above shows both.
Is this a color blindness test?
No — it's a simulator, not a test. It shows how images look with each type of CVD, which is great for checking designs and building empathy, but it can't diagnose your own vision. Genuine screening uses calibrated tools like Ishihara plates or the Farnsworth arrangement test, and a proper diagnosis comes from an optometrist. Want to check your own vision? Take our Ishihara-style color blind test.
Designing for color blindness
- Never rely on color alone — pair it with labels, icons, or patterns.
- Keep strong contrast between adjacent colors.
- Be careful with red/green status indicators; add a shape or text cue.