Color Blind Test

What this tool does

Many people go years without realising their colour vision differs from most, because you only know the colours you see. A simple test can give you an early, informal sense of whether you might have a colour vision deficiency, using the familiar plates of coloured dots with a number hidden inside them.

That is what this does. It shows you a series of test plates and asks what you can see in each, then gives you an indication of whether your responses suggest a possible colour vision deficiency. It is a quick way to check for awareness, not a medical assessment, and the sections below are clear about what it can tell you and where a professional is needed instead.

How to use it

1. Look at each plate. Look at each test plate and enter the number you can see in it.
2. Answer honestly. Report what you actually see, even if it seems unclear, rather than guessing at what you think is expected.
3. Read the indication. The tool tells you whether your answers suggest a possible colour vision deficiency.

Go through the plates one by one, entering what you genuinely see, and read the result as a rough indication rather than a verdict.

How it works

The test uses plates in the style devised by Ishihara, each a circle of coloured dots with a figure, usually a number, picked out in dots of a different colour. Someone with typical colour vision reads the figure easily, while someone with a colour vision deficiency may see a different figure, or none, because the colours that separate the figure from the background are ones they find hard to tell apart.

By showing several such plates and comparing your answers against what most people report, the test builds a picture of whether you may have difficulty distinguishing certain colours, most commonly reds and greens. It is looking at patterns across the plates rather than any single answer, which is how it forms a general indication of possible colour vision deficiency.

What colour blindness is

Colour blindness, more accurately called colour vision deficiency, means seeing certain colours differently from most people, usually finding some harder to tell apart. It is rarely a complete absence of colour; far more often it is a reduced ability to distinguish particular pairs, with red and green being the most common difficulty, and blue and yellow much rarer.

It arises from how the light-sensing cells in the eye respond to colour. Most people have three types tuned to different parts of the spectrum, and a deficiency comes from one type responding weakly or differently, which narrows the range of colours that can be separated. It is usually inherited and present from birth, it is more common in men than women, and it affects a noticeable share of the population, so it is far from unusual.

What the test plates show

Each plate is designed so that colour, and colour alone, separates the hidden figure from its surroundings. The dots are made in varied brightnesses and sizes on purpose, so that you cannot pick out the figure by lightness or shape; only by distinguishing the colours can it be read. That is what makes the plates a fair test of colour vision rather than of anything else.

Because of this design, the plates reveal difficulties that everyday life often hides. In daily situations there are usually other clues, brightness, position, context, that let someone with a colour vision deficiency get by without noticing anything is different. The plates strip those clues away and leave only the colour, which is why they can surface a difference that would otherwise go unnoticed.

Why take the test

The main reason is simple awareness. Knowing that you see colours differently explains a lot, from disagreements about what colour something is to difficulty with colour-coded charts or maps, and it lets you find ways to work around it. Many people feel a small sense of relief on discovering there is a name and a reason for something they had noticed but never understood.

It can also matter practically. Some occupations have colour vision requirements, and knowing early where you stand is useful, as is understanding why certain colour-based tasks feel harder for you than for others. For parents, an early informal check can flag that a child might see colours differently, which helps in explaining things gently and in letting teachers know. In all these cases, the value is in the awareness the test can prompt.

What the test can and cannot tell you

It is important to be honest about the limits. This is an informal screening for awareness, not a medical diagnosis. Its result depends on your screen, its colour settings, and the lighting around you, all of which can affect how the plates appear, so it can only ever suggest a possible deficiency rather than confirm one or measure its type and degree.

If the test suggests you might have a colour vision deficiency, or if you have reason to think you do regardless of the result, the right next step is a proper assessment by an optometrist or eye doctor. They use calibrated equipment and controlled conditions to give an accurate diagnosis and to identify exactly which type and how strong it is. Treat this tool as a prompt that might lead you to seek that assessment, not as a substitute for it.

Questions people ask

How does the test work?

You look at plates of coloured dots with a number hidden in them and report what you see. Your answers across the plates give an indication of possible colour vision deficiency.

Is this a medical diagnosis?

No. It is an informal screening for awareness. Its accuracy depends on your screen and lighting, so it can only suggest a possible deficiency, not confirm or measure one.

What if it suggests I am colour blind?

See an optometrist or eye doctor for a proper assessment. They use calibrated tests to give an accurate diagnosis and to identify the exact type and degree.

Is colour vision deficiency common?

Yes, it affects a noticeable share of people, more often men than women, and is usually inherited. Red-green difficulty is the most common form.

References

1. Ishihara test, the coloured-dot plates for colour vision. Wikipedia. https://en.wikipedia.org/wiki/Ishihara_test
2. Color blindness, colour vision deficiency and its types. Wikipedia. https://en.wikipedia.org/wiki/Color_blindness
3. Color vision, how the eye senses colour. Wikipedia. https://en.wikipedia.org/wiki/Color_vision