Color Blindness Test: Check Your Colour Vision
Read the numbers hidden in dotted plates, then see how colours look with common types of colour vision difference. A screening aid, not a diagnosis.
Which number do you see?
Answer within a few seconds, from your normal viewing distance, without tilting the screen.
Your screening result
This is a screening aid, not a medical diagnosis. Screen colour and brightness affect the plates. If you have concerns, an optometrist can run a full, calibrated colour vision assessment.
See colour through different eyes
The same colours simulated for the most common types of colour vision difference.
Around 1 in 12 men and 1 in 200 women have some form of colour vision difference, and many do not realise it until a game, a chart or a traffic light catches them out. This colour blindness test gives you nine dotted plates, each hiding a number. Some numbers are easy for everyone. Others only stand out if your eyes separate red from green, or blue from yellow, the way most people’s do.
The plates are generated fresh every time you take the test, so you cannot memorise them. When you finish, you get a clear summary and a plate-by-plate review. Below the test, a simulator shows the same colours as they appear with each common type of colour vision difference.
How to take the colour blindness test
- Set your screen to normal brightness and turn off night mode, blue light filters and any colour filters.
- Sit at your usual distance and look at the first plate. It is a practice plate everyone should be able to read.
- Choose the number you see, or I see no number if nothing stands out. Answer within a few seconds.
- Continue through all nine plates. Do not tilt the screen or zoom in.
- Read your result and the review, then explore the simulator below.
How the test plates work
Hiding a number in colour
Each plate is a circle filled with hundreds of dots of different sizes. The dots that form the number come from one set of colours, the background dots from another. Crucially, both sets have similar brightness. If your eyes tell the two hues apart, the number jumps out. If those hues look alike to you, the number blends into the background.
Red-green and blue-yellow plates
Seven plates use orange, red, olive and green combinations that people with red-green differences find hard to separate. One plate uses blue and green tones associated with blue-yellow differences. The first plate uses strongly contrasting colours as a control.
Why they change every time
The number, the dot layout and the answer choices are randomised on each attempt. That prevents learning the answers and lets you retake the test to confirm a pattern.
Types of colour vision difference
| Type | Affects | How common |
|---|---|---|
| Deuteranomaly and deuteranopia | Green sensitive cones, red-green confusion | Most common, around 6% of men |
| Protanomaly and protanopia | Red sensitive cones, reds look darker | Around 2% of men |
| Tritanomaly and tritanopia | Blue sensitive cones, blue-yellow confusion | Rare, affects men and women equally |
| Achromatopsia | No colour perception | Very rare |
Red-green differences are inherited on the X chromosome, which is why they are far more common in men. Many people have a mild anomaly rather than complete loss, so they see colour, just a narrower range of it.
Understanding your result
- Typical colour vision. You read every plate. There is no sign of a common colour vision difference on this screen.
- Mostly typical. One or two misses. These often come from screen settings, glare or a rushed answer. Retake the test and see if the same kind of plate trips you up.
- Possible red-green difference. Three or more red-green plates were missed, a pattern typical of protan or deutan vision.
- Check your screen. The practice plate was missed, so the display itself is likely the problem.
This is a screening aid, not a diagnosis. Screens vary in colour accuracy, and a proper assessment uses printed or calibrated plates under controlled light. An optometrist can confirm the type and degree.
Your screen affects the result
Unlike printed plates, an online test depends on your display. A strong colour tint, very low brightness, a night mode filter or a panel running in a vivid preset can change how plates look. If your result surprises you, check your display with the monitor test and make sure no pixel faults sit in the middle of the screen using the dead pixel test. Your scaling and resolution appear in the screen resolution test.
Using the colour vision simulator
The simulator shows a rainbow strip and ten common colours as they appear with protanopia, deuteranopia, tritanopia and achromatopsia. It is useful for designers checking whether charts and interfaces rely on colour alone, for gamers choosing team colours, and for friends and family who want to understand what someone with a colour vision difference actually sees.
Games and colour vision
Many games offer colourblind modes that shift reds and greens toward blues and oranges. If your result points to a red-green difference, turn those modes on. Enemy outlines and health bars become much easier to read, which can help as much as training your reaction time.
Tips for living with a colour vision difference
- Turn on colourblind modes in games, apps and your operating system accessibility settings.
- Label cables, folders and charts with text or patterns, not just colour.
- Ask for colour vision details in job medicals that require it, such as aviation or electrical work.
- Use phone apps that name colours through the camera when shopping or matching clothes.
- Retake this test on a second device now and then, so a single screen never decides what you believe about your eyes.
Frequently asked questions
How accurate is an online color blindness test?
It is a good screening tool, but screens vary in colour accuracy and brightness. Use it as an indication, and see an optometrist for a calibrated assessment.
What does it mean if I missed the practice plate?
Everyone should read the practice plate, so missing it usually points to screen settings such as low brightness or a colour filter, rather than your vision.
Is red-green colour blindness the most common type?
Yes. Deuteranomaly, a reduced sensitivity to green light, is the most common type, followed by protanomaly.
Can colour blindness be cured?
Inherited colour vision differences cannot be cured, but special tinted glasses can improve contrast between some colours for some people, and colourblind modes in software help a great deal.
Why are the numbers different each time?
Plates are generated randomly on each attempt so you cannot learn the answers. That makes retaking the test a fair way to confirm a result.
What is the most common type of colour blindness?
Deuteranomaly, a reduced sensitivity to green light, is the most common, especially among men.
Can women be colour blind?
Yes, although red-green colour blindness is much rarer in women because it is inherited on the X chromosome.
Does screen brightness affect the result?
Yes. Very dim or overly bright screens and colour filters can make plates harder to read.
Can children take this test?
Yes, if they can read numbers. For school or medical decisions, an eye care professional should confirm the result.
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