Color Blind Test Online

A free, scientifically-grounded color blindness screening you can take right in your browser. It combines pseudoisochromatic Ishihara plates generated on genuine color-vision confusion lines, the Farnsworth D-15 arrangement test with Vingrys & King-Smith scoring, and a Cambridge-style discrimination check — to estimate your color vision type (protan, deutan or tritan) and its severity.

How to take the color blind test

1
Check your screen

Confirm you can see distinct red, green and blue squares. Raise brightness and disable color filters and night mode.

2
Read the Ishihara plates

For each plate of colored dots, type the number you see or press "Can't see a number".

3
Arrange the colors (D-15)

From the reference cap, chain the caps by closest color. This reveals subtle discrimination errors and the confusion axis.

4
Find the ring gap

In the discrimination stage, tell us which side a faint colored ring is open on as it gets progressively harder along each color axis.

5
Review your results

See your estimated type, severity and confidence, with a per-test breakdown, and download a PDF report for your eye doctor.

Screen your color vision with Ishihara plates, the D-15 arrangement test and a confusion-line discrimination check

Ophthalmology

Three complementary tests in one screening — built on the same confusion-line color science used by clinical tools, run entirely in your browser.

  • Ishihara plates generated on real color-vision confusion lines — not random hues.
  • Farnsworth D-15 arrangement, scored with the Vingrys & King-Smith method.
  • Confusion-line discrimination screening across red, green and blue axes.

For best results, use a screen with good color reproduction at full brightness in a well-lit room. Turn off night mode, True Tone and blue-light filters, which shift colors and can invalidate the test.

This is a screening tool, not a clinical diagnosis. Screen calibration, lighting and display quality affect the result — for medical advice, consult an ophthalmologist.

Screen Check

Make sure you can see three clearly different colored squares below: red, green and blue. If they look similar or washed out, raise your screen brightness and disable any color filters before continuing.

You should also see a smooth gradient from black to white above, with distinct steps near both ends — that means your brightness and contrast are set sensibly.

This is a screening tool, not a clinical diagnosis. Screen calibration, lighting and display quality affect the result — for medical advice, consult an ophthalmologist.

Why there is no on-screen anomaloscope. A clinical anomaloscope matches a yellow against a mix of monochromatic red and green light — wavelengths a regular RGB screen physically cannot emit. Any browser "anomaloscope" slider is therefore not a real Rayleigh match and has no diagnostic value, so we leave it out. Instead, the third stage uses a confusion-line discrimination test (in the spirit of the Cambridge Colour Test), which is scientifically valid on a screen because it depends on the direction of the color difference, not on exact wavelengths.

Features

Real confusion-line plates
Every plate's figure and background are paired so the number is obvious to normal vision but collapses for the targeted deficiency — verified by simulating the rendered pixels, not random colors.
Three complementary tests
Ishihara screening, the Farnsworth D-15 arrangement test, and a confusion-line discrimination check together estimate type and severity.
Type and severity
Get protan, deutan or tritan with a severity estimate and a confidence level that reflects how well the three tests agree.
PDF report
Download a clear summary of your results to share with an eye-care professional.

Frequently Asked Questions

How accurate is an online color blind test?

It is a screening, not a diagnosis. Because it relies on the relative color difference between dots — which survives moderate display variation — it is a good first check, but screen calibration, lighting, blue-light filters and display quality all affect the outcome. A clinician with physical Ishihara/HRR plates or an anomaloscope is needed to confirm a result.

What types of color blindness does it detect?

It screens for the three deficiency axes: protan (red-weak), deutan (green-weak) and tritan (blue-weak). Red-green deficiencies are by far the most common; tritan is rare and most often acquired.

Why don't you include an anomaloscope?

A real anomaloscope needs monochromatic red and green light that an RGB screen cannot produce, so an on-screen "anomaloscope" slider has no diagnostic meaning. We replace it with a confusion-line discrimination test, which is valid on a screen because it depends on the direction of the color difference rather than exact wavelengths.

Can I take the test on my phone?

Yes, on any device with a modern browser. For the most reliable result, raise the brightness and turn off night mode, True Tone and blue-light filters, which shift colors away from the values the test assumes.

Is this a medical diagnosis?

No. It is an educational screening tool. If it suggests a color vision deficiency, or if you have concerns, see an ophthalmologist or optometrist for a clinical examination.

How do you rate this tool?

Thank you for your rating!
Want to share more? Leave a comment!
Thank you! Your comment will appear after moderation.
Who is this tool for?
♿ Accessibility Users 🏥 Healthcare Professionals
Published Updated Authors: