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At what age can you tell if a child is color blind?


Color blindness, also known as color vision deficiency, is the decreased ability to see color or differences between colors. It most often involves colors red, green, blue or mixtures of these colors. There are different types of color blindness and it can affect people differently. Color blindness can be inherited (genetic) or acquired by disease or injury to the eye, optic nerve or parts of the brain. Very rarely, color blindness is a side effect of some medications.

Some quick facts about color blindness:

  • About 1 in 12 men (8%) and 1 in 200 women are color blind.
  • Color blindness almost always is inherited and present at birth.
  • Red-green is the most common type of inherited color blindness.
  • Color blindness does not get worse over time.
  • People who are color blind are not “color blind” – they can still see colors, but they have difficulty differentiating between some colors.
  • Color blindness can make some educational activities and daily tasks more difficult.
  • There are ways to manage and cope with color blindness.

Color vision deficiency can be detected through different screening and testing methods. Early screening and testing allows for appropriate accommodations and aids to meet a color blind child’s learning needs.

When can color blindness be detected in children?

Color blindness can be detected and diagnosed at different stages of a child’s development using various screening and testing techniques:

Birth to 3 years

  • Watch for signs and behaviors that may indicate color vision issues:
    • Not responding to some colors.
    • Mixing up colors frequently.
    • Avoids coloring activities.
    • Difficulty matching colors.
    • Poor performance with color-related tasks.
  • Discuss any concerns with the child’s pediatrician.
  • Formal testing is not typically done this early.

Preschool age (3 to 5 years)

  • Screening can be done using age-appropriate colorful picture books and games.
  • The Ishihara color test uses a series of colored circles, called Ishihara plates, with embedded numbers visible to those with normal color vision.
  • The child is asked to identify or trace the numbers they see. Difficulty seeing the numbers indicates possible color vision issues.
  • The pediatrician may do additional screening tests during annual well-child exams.

Early elementary school (6 to 7 years)

  • School vision screenings include color vision assessment.
  • Classroom teachers can observe color recognition skills.
  • Formal color vision testing can be done if issues are suspected.

Older children

  • Testing should be done if there are indications of color blindness.
  • Genetic testing can confirm inherited color blindness.
  • Repeated issues with colors in school work may prompt referral for evaluation.

The American Academy of Ophthalmology recommends testing all children for color blindness at age 5. But in practice testing is often done when color vision issues are first noticed by parents, teachers or the pediatrician.

What are the different tests for determining color blindness?

There are several color vision tests that can detect color blindness and help determine the type and severity. Testing should be done under proper lighting conditions. The most common tests include:

Ishihara Color Test

  • Uses colored plates with embedded patterns of dots visible to those with normal color vision.
  • Often used for screening and testing red-green color deficiencies.
  • Can be used for preschool aged children up to adults.
  • Does not detect subtle color differences.

Farnsworth D-15 Test

  • Arranges 15 colored caps in order of hue.
  • Tests ability to detect color differences in the red-green range.
  • Suitable for children ages 5 and up.

Panel D-15 Test

  • Matches colored caps to a reference cap.
  • Sensitive test that detects subtle color variations.
  • Useful for determining extent of color deficiency.
  • Recommended for children 8 years and older.

Lantern Test

  • Matches shades of colored lights.
  • Helps classify type and severity of color blindness.
  • Requires focused attention span.
  • Best for children over age 8.

Hardy-Rand-Rittler (HRR) Test

  • Matches colored plates viewed under fluorescent light.
  • Detects red-green color deficiencies.
  • Recommended for testing beyond preschool years.

Genetic Testing

  • Provides definitive diagnosis of inherited color blindness.
  • Involves taking a blood or saliva sample for DNA analysis.
  • Useful if diagnosis from vision tests is unclear.
  • Helps determine likelihood of passing on color blindness.

The type and combination of color vision tests used depends on the child’s age, development and cooperativeness. Testing under the guidance of an eye care professional is recommended for accurate results.

Tips for detecting color blindness

Here are some tips parents and teachers can use to watch for early signs of possible color vision deficiency:

  • Note if child confuses colors frequently, like blue and purple or red and green.
  • Look for difficulty matching colors during games, puzzles and art activities.
  • Watch if child avoids coloring, has unusual color combinations or stays “inside the lines”.
  • Pay attention if child has trouble with color concept development like sorting by color.
  • Notice if child has delayed ability to name colors compared to peers.
  • Check if child has difficulty with colors in computer games or tablet apps.
  • See if child mixes up colored objects, clothes or crayon labels.
  • Monitor if child has reading difficulties related to color coding.

Consult the pediatrician if color vision issues are suspected, especially if there is a family history of color blindness. Timely screening and testing ensures needed vision aids and classroom adaptations are provided.

Why is early detection of color blindness important?

There are several reasons detecting color vision deficiencies early in childhood is beneficial:

  • Access vision aids and adaptive skills: Children can be taught compensatory strategies and provided tools to work with their color blindness from an early age.
  • Make classroom adaptations: Teachers can make adjustments like using labeling, lighting and materials to support the child’s learning needs.
  • Boost learning and development: Diagnosis allows customized support for the child to learn colors and minimize impact on skills like reading maps or graphs.
  • Improve self-esteem: Knowing about color blindness helps the child understand their vision and reduces self-blame for color-related difficulties.
  • Open communication: Testing enables discussion of color blindness between the child, family and school to aid the child’s adjustment.
  • Enhance safety: Certain color-coded warnings and hazards can be adapted for color deficient children to improve safety.
  • Plan for future: Advance knowledge of color blindness allows preparing for future education, career choices and other aspects of life.

Diagnosing color blindness early is key to providing appropriate support to the child during formative academic years. Timely testing and intervention helps the child thrive despite color vision challenges.

What are the challenges of color blindness in children?

Color blindness can pose some difficulties for children in educational activities and everyday life. Common challenges include:

Education challenges

  • Difficulty identifying colors during lessons involving coloring, maps, charts, etc.
  • Trouble distinguishing color-coded information in textbooks and workbooks.
  • Mixing up color-labeled objects and materials in class activities.
  • Misinterpreting colored diagrams, graphs and illustrations.
  • Issues correctly using colored learning toys and games.
  • Color-based arts and crafts projects prove frustrating.

Developmental challenges

  • Delayed ability to comprehend and recognize colors.
  • Problems learning color names, labels and categorization.
  • Difficulty with color-coded puzzles, sorters and blocks.
  • Trouble identifying colors of familiar objects like grass, sun or sky.

Everyday challenges

  • Confusion trying to match or select clothing colors.
  • Difficulty playing color-based games with friends.
  • Issues discerning traffic lights or warning colors.
  • Problems identifying correct colors of foods and drinks.
  • Trouble telling ripeness of some fruits/vegetables by color.

Social and emotional challenges

  • Embarrassment about color blindness.
  • Fear of trying new color-related activities/games.
  • Worries about keeping up in classwork.
  • Feeling left out of discussions involving colors.
  • Teasing from peers about mixing up colors.

Early detection coupled with appropriate support and adaptation allows the color blind child to manage these challenges and reach their potential.

How can parents and teachers support a color blind child?

Here are some tips for parents and teachers to help a color blind child:

For parents

  • Learn about your child’s specific color blindness.
  • Find out what aids and adaptations can support your child.
  • Use names or labels for colors when talking or giving directions.
  • Choose brightly colored clothes that are easier to match.
  • Use a color-identifying app to help verify clothing colors.
  • Teach strategies for choosing ripe produce like feeling softness.
  • Allow use of a light or filter overlay for reading colored text.
  • Explain your child’s color vision to teachers and caregivers.

For teachers

  • Learn the type and severity of the student’s color blindness.
  • Make classroom labels and signs colorblind friendly.
  • Use shapes and patterns along with colors to encode information.
  • Allow student to use a color reading ruler or filter overlay.
  • Reduce reliance on color-coding in instructional materials.
  • Give verbal directions for color tasks (“sky color” vs. “blue”).
  • Allow alternative color options for assignments.
  • Seat student strategically for the board and projector screen.
  • Print handouts on non-glossy paper to reduce glare.

With some adjustments by parents and teachers, a child with color blindness can thrive socially, academically and emotionally.


Color blindness is a common vision condition that makes it hard to distinguish between some colors. While color vision deficiencies are usually present at birth, detection in early childhood is vital for providing adaptive support. Screening preschoolers with picture books and games can identify potential color blindness. Formal testing is recommended starting around ages 5-6 years, or sooner if problems are observed. Diagnosing color blindness early allows parents and teachers to implement tools, aids and strategies to help the child adapt. With proper assistance, children with color blindness can achieve academic, career and life successes on par with their peers.