Ishihara Color Blind Test

The Ishihara test is the most widely used screening test for red-green color deficiency. Identify numbers hidden within colored dot patterns.

Ishihara Color Blind Test

This test uses Ishihara plates to screen for red-green color blindness. You'll be shown colored dot patterns with hidden numbers.

•Look at each image and identify the number you see
•Type the number and press Enter or click Submit
•If you can't see a number, click Skip

What is the Ishihara Test?

The Ishihara test was designed by Dr. Shinobu Ishihara in 1917 and remains the gold standard for color blindness screening. It consists of circular plates containing colored dots arranged to form numbers or patterns.

People with normal color vision can see the numbers clearly, while those with red-green color deficiency may see different numbers or no numbers at all. The test is particularly effective at detecting:

Protanopia - Red blindness
Protanomaly - Red weakness
Deuteranopia - Green blindness
Deuteranomaly - Green weakness

Color vision comparison chart showing how colors appear with normal vision, Protanopia, Deuteranopia, and Tritanopia

How to Take the Test

1. Start the Test

Click the "Start Test" button above. Choose between the 14-plate quick test or the full 38-plate version.

2. Identify Numbers

Look at each plate and enter the number you see. If you cannot see a number, click "I can't see".

3. Get Results

After completing all plates, receive your result indicating color vision status and type of deficiency, if any.

Types of Ishihara Plates

Ishihara plate example showing the number 12 - demonstration plate visible to everyone

Ishihara plate example - vanishing plate for red-green color blindness detection

Ishihara plate example - transformation plate showing different numbers based on color vision

Demonstration Plates

The first plate is visible to everyone, regardless of color vision. It serves as a practice plate to introduce you to the test format and does not count toward your score.

Transformation Plates

These plates show different numbers to people with normal vision versus those with color deficiency. A person with red-green deficiency will read a different number than someone with normal vision.

Vanishing Plates

The numbers on these plates are only visible to people with normal color vision. If you have a color vision deficiency, the number will be invisible or very difficult to see.

Hidden Digit Plates

These special plates contain numbers that are only visible to people with color vision deficiency. Those with normal vision cannot detect the hidden figures.

Diagnostic Plates

These plates help determine the specific type and severity of color blindness, distinguishing between Protanopia (red-blind) and Deuteranopia (green-blind).

Sources

National Eye Institute (NEI) — Overview of color blindness types, causes, and diagnosis
American Academy of Ophthalmology (AAO) — Clinical information on color vision deficiency and testing methods
National Health Service (NHS) — Symptoms, causes, and management of colour vision deficiency
Shinobu Ishihara — Wikipedia — History of the Ishihara test and its creator
MedlinePlus (U.S. National Library of Medicine) — Medical guide on color blindness diagnosis and treatment

Frequently Asked Questions

The 14-plate test is a quicker screening that can detect color vision deficiency in most cases. The full 38-plate test provides a more comprehensive assessment, including the type and severity of the deficiency.

This online test is a screening tool, not a clinical diagnosis. Screen calibration, brightness, and ambient lighting can affect results. For a definitive diagnosis, consult an eye care professional.

The Ishihara test detects red-green color deficiencies, including Protanopia (red-blind), Protanomaly (red-weak), Deuteranopia (green-blind), and Deuteranomaly (green-weak). It does not test for blue-yellow deficiency (Tritanopia).

The Ishihara test requires the ability to recognize numbers, so it is suitable for children who can read digits (typically age 6+). For younger children, our Kids Color Blind Test uses animal shapes instead of numbers.

Online tests provide a good screening indication but are not as accurate as printed Ishihara plates used in clinical settings. Display quality, color calibration, and viewing conditions can all affect results.