The Ishihara test is indeed a diagnostic tool used to detect color blindness, particularly red-green color blindness. This test uses the technique of pseudo isochromatic plates, called Ishihara charts, to diagnose color vision deficiency. The Ishihara chart depicts a figure or a digit using various small dotted circles of red, green, and blue hues. The test aims to identify the figure hidden in the Pseudoisochromatic chart.

In the Ishihara test, A normal-visioned person will be able to identify the figures depicted in the Ishihara chart. While a color-blind person will fail to do so. A color-blind will see a different figure or number, or no figure at all, depending on the type of color blindness he/she suffers. A person scoring a minimum of 12 out of 14 (excluding the demonstration plate) is declared to be normal vision. In contrast, a score below 12 out of 14 will conclude a person to be color blind.

The online color blind test is a revolutionary diagnostic tool for color blinds. This is a simple, less time-consuming and handy testing tool to be tested anywhere and anytime. Hence, it wouldn't be wrong to assert that the  Ishihara test is the best color blindness test. The test not only tests for CVD but also the type of color blindness a person is suffering from and that too without any medical interventions.

 Ishihara test

The History Of The Ishihara Test?

The Ishihara test is named after a Japanese professor, Dr Shinobu Ishihara from Tokyo University. Being an ophthalmologist, Ishihara was given the task to design a diagnostic test to screen for color vision deficiency (CVD) as a screening test for soldiers during World War I. So, with the help of the existing 'stilling test', which included the use of pseudo isochromatic plates, he designed Ishihara charts to diagnose color blindness.

The literal meaning of pseudo isochromatic plates is 'false-same-colored' plates. Ishihara developed certain circular dotted charts depicting figures to be identified using the principle of Pseudoisochromatism. He used 38 different types of pseudo-isochromatic plates to diagnose different types of color blindness and normal vision.

How to take the test?

Click on 'take the test' to start the test.

A series of 25 Ishihara chart questions will appear as you answer them one after the other.

Answer the question by identifying the number that you can see in the Ishihara charts.You can also skip question by clicking on the “skip” button

After finishing all the questions, your result will be displayed mentioning the status of your color vision, type of color blindness in color blinds and severity.

A clear statistical report is displayed below the result which can be downloaded or shared to be rechecked by a professional.

Types of Ishihara plates

The test consists of a total of 38 plates. These 38 plates are grouped into six main types. The aim of differentiating them into these types is to diagnose CVD, color blindness, normal vision and their subtypes. The use and specialities of each type are discussed below. 

Demonstration Plate

The demonstration plate is the first plate in the Ishihara test. It is a chart mentioning a figure of 12. Sometimes, it can also mention a figure of 16 in the improved versions. This plate is visible to all persons whether color-blind or normal-visioned. As the name suggests, the purpose of this plate is for demonstration only. 

Transformation Plates

The transformation plate has an important differentiating purpose. Different figures are observed by the color-blind than the normal-visioned.

Vanishing Plates

In vanishing plates, No figure is visualized by the colorblind. Normally visioned people can however easily identify the figure in the vanishing plate.

Hidden Digit Plates

This plate has an exact opposite function to that of a vanishing plate. As the name suggests, a normal-visioned person is unable to see any figure on this plate, while a color-blind can identify the figure from the plate.

Diagnostic Plates

Diagnostic plates are acts as a differentiating test between different types of color blindness, ie. Protanopia, deuteranopia, protanomaly, deuteranomaly, etc. Different figures are observed by the patients suffering from different types of color blindness. For example, a red color-blind person will see a certain figure, while a green color-blind person will see another figure and so on.

Tracing Plates

In these plates, lines and curves are traced differently by the color blinds, normally visioned and the different types of color blinds. It does not involve the identification of figures or digits.

Benefits Of Taking Online Test


The Ishihara test is an online free to use tool to test for color blindness. A Hospital charges money for any type of eye test. An online test is always a free tool in contrast, thus making it an affordable option.

Privacy Protection

We follow a privacy protection policy, which doesn't leak or store any user data. Using the tool, a person can comfortably take the test at home and confine the results to themselves.

Accurate Result

This test is designed and produced by professionals in the medical and technological fields. Hence, the highest precision is provided And is as accurate as you may get from any diagnostic method for color blindness at the hospital.

Easy To Access

Being an online free-to-use tool, the color blind test is accessible at any time and from anywhere. It is an easy to use test. No application or software is required to be downloaded on the device as it is freely available on the web.

Frequently Asked Questions

What is a 21-plate Ishihara test?

The 21-plate test is a mini version of the conventional 38-plate Ishihara test. It does not yield the same results as the conventional one but is quicker than the latter.

Are all Ishihara Plates the same?

No, there is a wide variety of different types of Ishihara plates. They are diagnostic, demonstration, transformation, vanishing, hidden digit plates, and tracing plates. Each plate has a different role to play in the series of Ishihara plates. These different types of plates help yield the result of the color blind test, its subtype and severity in the test.

What If I Fail The Color Blind Test?

Failure in the test indicates that you have a color vision deficiency or color blindness. Sometimes, failure can also occur if you did not follow the instructions well before taking the test. You can retake the test by following proper instructions on the website as a confirmatory means. Retaking the test is easy and free on our website.

Is the Color Vision Test Suitable For All Ages?

Yes, the test is suitable for all ages above the year 5. A knowledge of figures or digits and shapes is required before taking the test and nothing more. It is easy to access and simple to use across all age groups.