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Color Blind Test Free online color vision screening

Read the number hidden in each dot plate. It takes about two minutes. This is a screening, not a diagnosis.

13 plates

No sign-up · Free

Each plate hides a number of one or two digits. Type what you see, or press No number if you see none.

Set up your screen first

  • Turn screen brightness up.
  • Turn off Night Shift, Night Light, blue light filters, color filters and dark reading modes.
  • Look straight at the screen from about arm's length, in normal room light.
  • Wear your usual glasses or contact lenses, but not tinted or color-correcting ones.

About this screening

The plates are drawn in your browser each time, so the numbers change and cannot be memorized. Four check red-green vision of the protan kind, four of the deutan kind, three blue-yellow (tritan), and two are control plates that anyone can read.

Keyboard: type the digits, Backspace to delete, Enter for the next plate.

Plates are drawn and scored in your browser. Nothing is uploaded and no account is needed.

How the test works

Plates made for each test

These are not the printed Ishihara plates. Each plate is drawn from scratch with random dot sizes and a random number, in the same style of dots that eye doctors use.

One color signal at a time

The eye has three kinds of cone cells, sensitive to long, medium and short wavelengths. In each plate, the number differs from the background for only one kind of cone. People who lack or have weak cones of that kind find the number hard or impossible to see.

Clear to faint

Each kind has plates from clear to faint, and the dots vary in brightness so the number cannot be found by lightness alone. Missing two or more plates of one kind is reported as a sign of a deficiency.

Types of color vision deficiency

Protan (red-weak)

The long-wavelength cones are missing or work differently. Reds can look darker and be confused with greens and browns. Severe cases are called protanopia, mild ones protanomaly.

Deutan (green-weak)

The medium-wavelength cones are missing or work differently. Greens, yellows and reds can be hard to tell apart. Together with protan, this makes up red-green color blindness, by far the most common kind.

Tritan (blue-yellow)

The short-wavelength cones are affected, so blue and green, or yellow and pink, can look alike. Inherited tritan deficiency is rare. Blue-yellow changes can also come with eye disease or a yellowing lens, which is a good reason to see an eye doctor.

Color vision deficiency (also called color blindness or daltonism) is much more common in men. The US National Eye Institute puts it at about 1 in 12 men. Seeing no color at all is rare. Source: National Eye Institute, checked 21 October 2026.

Reading your result

Your screen matters

Plates are calculated for a standard sRGB screen. Night modes, color filters, low brightness and uncalibrated displays shift the colors, which can hide numbers from people with normal color vision or reveal them to people with a deficiency.

One miss is normal

Faint plates are faint on purpose. Missing a single plate happens with normal color vision, so the result only reports a sign when two or more plates of one kind are missed.

Not a diagnosis

The result does not give a percentage or a medical grade. It tells you whether to ask about color vision at your next eye exam.

Color blind test FAQ

Is this the Ishihara test?

No. The Ishihara plates are a printed, copyrighted test used by eye doctors. This test draws its own plates in the same dotted style, with new numbers each time.

Can an online test diagnose color blindness?

No. Screens and lighting vary too much. Use this as a screening, and if it shows signs of a deficiency, ask an eye doctor or optometrist to test you with standardized plates in controlled light.

Why did I miss a plate when my color vision is fine?

The faint plates are close to the limit of what a normal eye can see on a phone or laptop screen, especially with low brightness or a night mode on. One missed plate is not reported as a sign. Try again with the screen settings in the checklist.

Can color blindness be cured, and do special glasses work?

There is no cure for inherited color blindness. The National Eye Institute says special glasses and contact lenses can help some people tell certain colors apart by increasing contrast, but they do not restore normal color vision.

Is my result saved or shared?

No. The plates and your answers stay on this page and are gone when you close or reload it.

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