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Color Blind Test: Are You Color Blind?

What is a color blind test?

A color blind test checks if you can accurately see colors. If you cannot pass the test, you have a form of color blindness. Most color blind tests are screening tests. They can detect color blindness but cannot determine how severe it is. More in-depth color blind testing is needed for that.

Color blind tests can identify children who might have trouble recognizing colors. This could be a factor in certain activities in school and at home.

These tests can also identify people who might struggle at jobs that require excellent color vision.

Screening tests for color blindness

A very popular screening test for detecting the presence of color blindness is the Ishihara Color Vision Test.

Shinobu Ishihara, a Japanese ophthalmologist, developed the test more than 100 years ago. It can quickly detect red-green color blindness (the most common color vision deficiency).

Ishihara plates used to screen patients for color vision problems. Someone with red-green color blindness may not see the red number in this example.

The Ishihara test consists of several circular images (or "plates"). Each image contains many dots of various colors, brightness and sizes.

A person who has normal color vision will be able to detect a visible number "hiding" within the array of dots.

But someone with red-green color blindness won't be able to see the number. Instead, they will see:

A random pattern of dots, or
A number different than the one seen by a person with normal color vision.

The complete Ishihara color blind test contains 38 plates. A shorter version of the test (with fewer plates) may be used during an eye exam to screen for color blindness.

The screening takes place under normal room lighting. If you need prescription glasses, you will wear them for this test.

If you fail the Ishihara Color Vision Test, your eye doctor will discuss this with you and whether a more detailed color blind test is recommended.

Detailed color blind tests

A screening test may be able to detect color blindness, but a more detailed color blind test is needed to measure how severe the condition is.

The most popular in-depth color blind test is the Farnsworth-Munsell 100 Hue Test.

The Farnsworth Munsell 100 Hue test identifies and quantifies color vision problems. (Image: Macular Pigment Research Group, Waterford Institute of Technology)

This test consists of four trays containing many small disks of varying hues. Each tray has a colored reference disk at one end. You must arrange the disks in each tray to create a continuous sequence of color change.

This test should take place under room lighting that simulates natural daylight.

Each colored disk has a number on the bottom that enables the tester to compare the results against a key. This comparison determines the type and severity of color blindness.

A shorter version of the Farnsworth-Munsell 100 Hue Test — called the D15 Test — contains 15 colored disks. Like the Ishihara test, the D15 test is for color blindness screening only.

SEE RELATED: Achromatopsia

Online color blind tests

Many color blind tests are available online. Most of these tests are versions or variations of the Ishihara screening test for color blindness.

Be aware that these online versions may be less accurate, based on the color accuracy of your display.

For the most accurate color vision testing, see your eye doctor.

Who should take a color blind test?

Everyone should take a color blind test at least once in their lifetime.

Color blind screening tests are especially important for young children. This is because some learning tasks in school may involve color detection or matching.

For adults, excellent color perception is required for certain technical and manufacturing positions. It's even more important for anyone considering a profession that requires perfect color vision. Examples include:

Commercial artist
Marketing professional
Designer
Electrician

Though there's no cure for color blindness, having a color blind test to screen for the condition is very useful. Color blind tests can make you aware of any color vision problems you have so you can take appropriate measures to compensate for your color blindness.

In some cases, specially tinted color blind glasses can help people with color blindness see colors more accurately.

LEARN MORE about the different types of color blindness.