Types of color vision deficiency
| Type | What is affected | How common |
|---|
| Deuteranomaly / deuteranopia | Green-sensitive cones; reds and greens look similar | Most common form, mainly in men |
| Protanomaly / protanopia | Red-sensitive cones; reds can look darker | Common, mainly in men |
| Tritanomaly / tritanopia | Blue-sensitive cones; blues and yellows are confused | Rare, affects men and women equally |
| Monochromacy | Little or no color vision | Very rare |
How this test works
The plates use the same idea as classic pseudoisochromatic tests: a number drawn in dots of one color, surrounded by dots of a different color with similar brightness. The dots vary in size and shade, so you cannot find the number by brightness or shape alone. Some plates are designed to be easy for everyone (control plates), while others get more subtle.
Living with color vision deficiency
- Most phones and computers have color filters for color blindness in their accessibility settings.
- Labels, patterns and symbols help with charts, wires and maps that rely on color.
- Some careers, such as pilot, electrician or certain military roles, have color vision requirements; ask about the specific test they use.
Checking your screen instead of your eyes? Try the dead pixel test.
Last reviewed October 2026.
Frequently asked questions
Is this an official color blindness test?
No. It is a quick screening test with original dot plates made for this site. It can suggest whether you might have a color vision deficiency, but only an eye care professional can diagnose it, using calibrated tests in proper lighting.
How does the test work?
Each plate hides a number made of colored dots among dots of another color. The colors are chosen to have similar brightness, so the number stands out only through hue. People with typical color vision can read it; people with red-green or blue-yellow deficiency may find some plates hard or impossible.
Why does my screen matter?
Screens vary a lot in color and brightness, and features like night mode, blue light filters or color profiles change the colors. Turn those off, set brightness to a normal level and view the plates straight on for the fairest result.
How common is color blindness?
Red-green color vision deficiency affects about 1 in 12 men and about 1 in 200 women of Northern European ancestry. Blue-yellow deficiency is much rarer. Most color blind people see many colors, just with some colors harder to tell apart.
What should I do if I miss several plates?
Retake the test on a different screen. If you still miss several red-green plates, consider seeing an optometrist for a full color vision test, especially if your job or hobbies depend on telling colors apart.