Colour Blindness: 9 Smart Ways to Live Confidently

Colour blindness usually does not mean seeing the world in black and white. Most people with colour vision deficiency can see many colours, but some shades are harder to tell apart.

Red and green confusion is the most common pattern. Blue and yellow problems are less common, while complete loss of colour vision is rare.

For most people, inherited colour vision deficiency stays stable throughout life. People often adapt very well once they know which colours cause trouble and which tools make daily tasks easier.

Medical note: This article is for general information and education. It does not replace medical advice, diagnosis, or treatment.

I am not a dermatologist or a doctor, and this content does not replace professional medical advice. What I share comes from real life experience, extensive research, and consultation with healthcare providers. Always consult qualified medical professionals for diagnosis and treatment of any health condition.

When a Change in Colour Vision Needs Medical Attention

Colour vision that has been different since childhood is very different from colour vision that suddenly changes in adulthood.

Arrange an eye or medical assessment if you notice:

• Colour vision becoming different when it was normal before
• A new difference between the two eyes
• Colours suddenly looking washed out
• Red becoming noticeably less bright in one eye
• Colour changes with blurred or reduced vision
• Colour changes after an eye or head injury
• Colour changes after starting a new medicine
• Colour changes with eye pain
• Colour changes with new neurological symptoms

Acquired colour vision deficiency can occur with problems affecting the retina, optic nerve, brain, lens, or certain medicines.

A new colour vision change is therefore not something to diagnose with an online colour test alone.

What Is Colour Blindness?

Colour blindness is the common name for colour vision deficiency.

The National Eye Institute defines it as seeing colours differently from most people or having trouble telling some colours apart.

Very few people with colour vision deficiency see no colour at all.

A person may instead confuse:

• Red and green
• Green and brown
• Red and brown
• Blue and purple
• Blue and green
• Yellow and pale pink

The exact pattern depends on the type of colour vision deficiency.

For a wider look at vision and eye care, visit the NextFitLife Eye Health and Vision Hub.

How Normal Colour Vision Works

Colour vision begins in the retina.

The retina contains light sensing cells called rods and cones. Rods help mainly with dim light vision, while cone cells are important for colour and fine detail.

Most people have three types of cone cells that respond most strongly to different parts of the visible light spectrum.

The brain compares the signals from these cones and creates the colours you perceive.

When one cone system works differently or is missing, certain colours become harder to distinguish.

The Main Types of Colour Blindness

The most useful way to understand colour blindness is by the colour system affected.

1. Deuteranomaly

Deuteranomaly is a common form of red green colour vision deficiency.

The green sensitive cone system works differently, so greens may look more like reds or browns and some shades become difficult to separate.

This type is often mild.

2. Protanomaly

Protanomaly affects the red sensitive cone system.

Red may appear less bright, and red, orange, yellow, green, and brown shades may be harder to tell apart.

3. Deuteranopia

Deuteranopia means the normal green cone signal is absent.

This produces a stronger red green colour vision deficiency than deuteranomaly.

4. Protanopia

Protanopia means the normal red cone signal is absent.

Red can appear darker than expected, and red green distinctions can be difficult.

5. Tritanomaly

Tritanomaly is a rare blue yellow colour vision deficiency.

Blue and green may be difficult to tell apart, and yellow may sometimes look more like red or pink.

6. Tritanopia

Tritanopia is a stronger blue yellow deficiency.

Blue and green may be confused, while yellow may be confused with violet or pale gray.

7. Achromatopsia

Achromatopsia is rare and much more severe.

People with complete achromatopsia have little or no useful colour vision and often have other symptoms such as:

• Strong light sensitivity
• Reduced visual acuity
• Nystagmus

This is very different from common red green colour blindness.

Colour Blindness Types at a Glance

Type	Main Colour Difficulty	Typical Pattern
Deuteranomaly	Red and green	Green response altered
Protanomaly	Red and green	Red response altered
Deuteranopia	Red and green	Green cone signal absent
Protanopia	Red and green	Red cone signal absent
Tritanomaly	Blue and yellow	Blue cone response altered
Tritanopia	Blue and yellow	Blue cone signal absent
Achromatopsia	Most or all colour	Severe cone dysfunction

Is Colour Blindness Genetic?

Often, yes.

Most common red green colour vision deficiencies are inherited.

They are commonly linked to genes on the X chromosome, which helps explain why red green colour deficiency is much more common in males.

A person can have inherited colour blindness even when their parents appear to have normal colour vision.

Blue yellow deficiencies are much rarer and follow different genetic patterns.

Inherited Versus Acquired Colour Vision Deficiency

This distinction matters.

Inherited Colour Vision Deficiency

Inherited colour blindness is usually:

• Present from childhood
• Similar in both eyes
• Stable over time
• Not associated with sudden loss of visual acuity

Acquired Colour Vision Deficiency

Acquired colour vision deficiency develops later.

Possible causes include:

• Optic nerve disease
• Retinal disease
• Cataracts
• Some neurological conditions
• Eye injury
• Certain medicines or chemicals
• Age related changes

Acquired colour changes may affect one eye more than the other and may worsen over time.

This is why a new colour vision change deserves proper assessment.

Can Cataracts Change Colour Vision?

Yes.

A cataract can gradually make colours look duller, browner, or more yellow.

Blue shades may become harder to distinguish because the cloudy natural lens absorbs and scatters more short wavelength light.

After cataract surgery, some people notice that colours look brighter or cooler because the cloudy lens has been removed.

This is acquired colour perception change, not inherited colour blindness.

How Is Colour Blindness Tested?

An eye care professional can use several tests depending on what needs to be measured.

Ishihara Test

The Ishihara test is one of the best known colour vision tests.

It uses circles filled with coloured dots. A number, path, or shape is hidden within the dots.

People with normal colour discrimination may see one figure, while people with red green colour vision deficiency may see a different figure or no figure.

Ishihara plates are mainly designed to detect red green deficiencies.

HRR Colour Test

The Hardy Rand Rittler test, often called HRR, can test both red green and blue yellow deficiencies.

It may also help grade severity.

Colour Arrangement Tests

In a colour arrangement test, you arrange coloured caps or tiles in a gradual colour sequence.

Tests such as the Farnsworth D15 can help identify the pattern and severity of colour discrimination problems.

Anomaloscope

An anomaloscope is a more specialized device used to measure certain red green colour vision deficiencies in detail.

It is often used in research or specialist occupational testing.

Can You Trust an Online Colour Blindness Test?

Online colour tests can be useful as a first check, but they have limits.

Your result can change because of:

• Screen quality
• Brightness
• Colour calibration
• Night mode
• Blue light filters
• Room lighting
• Image compression
• Viewing angle

An online test should therefore be treated as screening rather than a final diagnosis.

If colour vision matters for school, driving, work, licensing, or safety, use a properly administered validated test.

What Happens During a Professional Colour Vision Test?

The clinician will usually ask about:

• Whether colour problems have existed since childhood
• Whether one eye seems different from the other
• Family history
• Medicines
• Eye disease
• Eye or head injury
• Work requirements

The test may be performed one eye at a time.

If the colour vision problem appears acquired, the eye professional may also assess:

• Visual acuity
• Pupils
• Retina
• Optic nerve
• Visual field
• Eye pressure

Is There a Cure for Colour Blindness?

There is currently no established treatment that restores normal colour vision for common inherited red green colour blindness.

Most people do not need medical treatment.

Instead, they learn strategies that remove colour as the only source of information.

For acquired colour deficiency, treating the underlying cause may sometimes improve colour perception.

For example, cataract surgery may improve colour appearance when lens clouding is the cause.

Do Colour Blind Glasses Work?

Some tinted lenses are marketed as colour blind glasses.

These filters can alter the contrast between certain wavelengths of light. For some users, that makes selected colours easier to tell apart.

However, they do not repair missing or altered cone cells.

They do not give everyone normal colour vision, and results vary by type of deficiency, lighting, and task.

Can Colour Blindness Affect Children at School?

Yes, especially when teachers or parents do not know it is present.

A child may understand the lesson but struggle when information is coded only by colour.

Examples include:

• Colour coded maps
• Graphs and charts
• Science diagrams
• Traffic light worksheets
• Art lessons
• Electrical diagrams
• Matching games

A child may be incorrectly described as careless when the real problem is that two colours look very similar.

Helpful Classroom Changes

• Label colours with words
• Use symbols as well as colour
• Use patterns and textures
• Use strong contrast
• Avoid red and green as the only difference
• Allow the child to ask which colour is being used

These adjustments help without lowering academic expectations.

Colour Blindness and Careers

Most jobs are open to people with colour vision deficiency.

However, some safety critical roles may have formal colour vision standards.

Examples can include certain jobs in:

• Aviation
• Rail transport
• Maritime work
• Electrical work
• Military services
• Emergency services

The exact rules differ by country, organization, licence, and job role.

Do not assume that being colour blind automatically excludes you from an entire career.

Check the current official standard for the specific role before making career decisions.

Can Colour Blind People Drive?

In many countries, people with common inherited colour vision deficiency can drive private vehicles.

Drivers often learn traffic signals by:

• Position
• Shape
• Brightness
• Context

However, licensing rules vary between countries and between private and commercial driving.

If a licence requires a colour vision standard, use the current rule from the licensing authority rather than relying on general online advice.

Colour Blindness and Traffic Lights

Traffic lights are easier to interpret because colour is not the only clue.

Standard vertical lights normally use:

• Red at the top
• Amber or yellow in the middle
• Green at the bottom

Horizontal systems use a consistent order as well.

Position and context therefore provide extra information when colour alone is difficult.

9 Smart Ways to Live Well With Colour Blindness

1. Label Important Colours

Use small written labels for items where colour matters.

This works well for:

• Clothing
• Paint
• Wires
• Folders
• Medication organizers

2. Organize Clothing by Known Sets

Create outfits you already know match well.

Store similar colours together or label difficult shades.

3. Use a Colour Identification App

Modern smartphones can identify colours through the camera.

This can help with clothing, paint, signs, maps, charts, and household items.

Apps are convenient, but lighting and camera quality can affect the result.

4. Use Symbols as Well as Colour

If you create spreadsheets, charts, calendars, or dashboards, do not rely only on colour.

Add:

• Labels
• Icons
• Shapes
• Patterns
• Line styles

This is good visual accessibility for everyone.

5. Increase Contrast

High contrast often matters more than the exact hue.

Dark text on a light background is usually easier to distinguish than two similarly bright colours.

6. Learn Position and Context

Many everyday systems use more than colour.

Traffic lights, status indicators, controls, and charts can often be read by position, symbols, labels, or sequence.

7. Tell Teachers or Employers When Colour Matters

You do not need to announce colour blindness in every situation.

But when a task depends heavily on colour, a simple explanation can prevent mistakes.

Useful adjustments are often small.

8. Use Accessible Digital Settings

Operating systems and apps increasingly include colour filters, high contrast settings, and accessibility modes.

Experiment with them and choose the option that makes information easier to separate.

9. Have New Colour Changes Checked

If your colour vision changes after years of being stable, do not assume inherited colour blindness has suddenly worsened.

An acquired cause should be considered.

How to Make Charts Colour Blind Friendly

This matters at school, work, and online.

A chart should never use colour as the only way to communicate meaning.

Less Accessible	Better Choice
Red line versus green line	Different colours plus solid and dotted lines
Colour only status	Colour plus icon and text label
Similar pastel shades	Strong contrast plus labels
Unlabelled pie slices	Direct labels or patterns

Can Colour Blindness Get Worse?

Common inherited red green colour blindness usually remains fairly stable.

If colour vision changes noticeably over time, an acquired condition may be involved.

Examples include:

• Cataract
• Optic nerve disease
• Retinal disease
• Neurological disease
• Medication effects

That is why worsening or newly unequal colour perception between the eyes should be checked.

Can Diabetes Affect Colour Vision?

Diabetes can affect the retina and other parts of the visual system.

Some people with diabetic eye disease can develop changes in colour discrimination.

New colour vision changes in a person with diabetes should not simply be blamed on inherited colour blindness.

Read our Eye Health and Diabetes guide for retinal warning signs and screening guidance.

Does Colour Blindness Affect Night Vision?

Common red green colour vision deficiency does not usually cause classic night blindness.

Night blindness has different causes, including cataracts, retinal disease, vitamin A deficiency, and refractive problems.

Severe inherited cone disorders such as achromatopsia can affect vision in more complex ways, including strong light sensitivity.

If darkness rather than colour is your main problem, read our Night Vision Problems guide.

Is Colour Blindness a Disability?

The answer depends on the person, the severity, local law, and the task.

Many people with common red green colour vision deficiency have few limitations in daily life.

Others may need adjustments when work or education depends heavily on colour discrimination.

The useful approach is to focus on function rather than labels.

If a task can be redesigned using symbols, text, patterns, or better contrast, the colour barrier often becomes much smaller.

Colour Blindness Myths Worth Dropping

Myth 1: Colour Blind People See Only Black and White

False. Most people with colour blindness see many colours but have difficulty separating specific shades.

Myth 2: Red Green Colour Blindness Means Red and Green Always Look Identical

No. The exact appearance depends on the type and severity of the deficiency.

Myth 3: Colour Blindness Glasses Cure the Condition

No. Filters can alter colour contrast for some people, but they do not restore normal cone function.

Myth 4: An Online Ishihara Test Gives a Final Diagnosis

No. Screens and lighting can change the test. Professional testing is more reliable when the result matters.

Myth 5: Colour Blind People Cannot Drive

Not generally. Many people with colour vision deficiency drive safely, although licensing rules vary by country and vehicle class.

Myth 6: Colour Blind People Cannot Work in Technical Careers

False. Most careers remain open. Some safety critical positions have specific colour vision standards.

Myth 7: Colour Blindness Always Starts in Childhood

No. Inherited forms usually do, but acquired colour vision deficiency can develop later because of eye disease, neurological disease, injury, cataracts, or certain medicines.

Myth 8: Colour Blindness Always Affects Both Eyes Equally

Inherited forms usually affect both eyes similarly. A new difference between the eyes may suggest an acquired problem and deserves assessment.

Conclusion: Colour Blindness Does Not Have to Limit Your Life

Colour blindness changes the way certain colours are distinguished, but it does not define intelligence, creativity, independence, or potential.

Most inherited red green colour vision deficiency stays stable throughout life. The most useful strategy is to understand your type, use more than colour when making decisions, and take advantage of labels, accessibility settings, apps, patterns, and strong contrast.

The important exception is a colour vision change that starts later or suddenly becomes different. That deserves an eye or medical assessment because an acquired cause may need treatment.

Your next step: if you have never had your colour vision properly tested, ask an eye care professional at your next examination. If your colour vision has recently changed, arrange an assessment rather than relying only on an online test.

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Frequently Asked Questions About Colour Blindness

What is colour blindness?

Colour blindness, or colour vision deficiency, means seeing some colours differently from most people or having difficulty telling certain colours apart. Most people with colour blindness still see many colours.

What is the most common type of colour blindness?

Red green colour vision deficiency is the most common type. Deuteranomaly is one of the most common inherited forms and affects the way green related colour information is processed.

What is the Ishihara test?

The Ishihara test uses coloured dot plates that contain numbers, shapes, or paths. It is mainly designed to screen for red green colour vision deficiency.

Are online colour blindness tests accurate?

Online tests can be useful for screening, but screen settings, brightness, colour calibration, filters, and room lighting can affect the result. A professionally administered test is better when the diagnosis matters for health, school, work, or licensing.

Can colour blindness be cured?

There is currently no established cure that restores normal colour vision in common inherited colour blindness. People usually adapt using labels, patterns, accessible design, apps, and other practical tools.

Do colour blind glasses work?

Colour enhancing glasses can change colour contrast and may make certain shades easier to distinguish for some people. They do not repair the underlying cone difference and do not give everyone normal colour vision.

Can colour blindness develop later in life?

Yes. Acquired colour vision deficiency can occur because of cataracts, retinal disease, optic nerve disease, neurological conditions, eye injury, or certain medicines. A new colour vision change should be professionally assessed.

Can colour blind people drive?

Many people with common colour vision deficiency can drive safely because traffic systems also use position and context. Licensing requirements vary by country and vehicle class, so current local rules should be checked.

Does colour blindness affect both eyes?

Inherited colour vision deficiency usually affects both eyes in a similar way. A new difference between the two eyes may suggest an acquired eye or optic nerve problem and should be assessed.

Is colour blindness more common in males?

Yes. Common inherited red green colour vision deficiencies are usually linked to genes on the X chromosome, which makes them much more common in males.

References and Sources

1. National Eye Institute. Color Blindness.https://www.nei.nih.gov/eye-health-information/eye-conditions-and-diseases/color-blindness
2. National Eye Institute. Color Blindness: Types.https://www.nei.nih.gov/eye-health-information/eye-conditions-and-diseases/color-blindness/types-color-blindness
3. NHS. Colour Vision Deficiency.https://www.nhs.uk/conditions/colour-vision-deficiency/
4. American Academy of Ophthalmology. What Is Color Blindness?https://www.aao.org/eye-health/diseases/what-is-color-blindness
5. MedlinePlus Genetics. Color Vision Deficiency.https://medlineplus.gov/genetics/condition/color-vision-deficiency/
6. American Optometric Association. Color Vision Deficiency.https://www.aoa.org/healthy-eyes/eye-and-vision-conditions/color-vision-deficiency

Medical disclaimer: I am not a dermatologist or a doctor, and this content does not replace professional medical advice. What I share comes from real life experience, extensive research, and consultation with healthcare providers. Always consult qualified medical professionals for diagnosis and treatment of any health condition.