Most common color blindness test
Red-Green Colorblind Test
This red-green colorblind test focuses on the most common color vision deficiency axis. It uses Ishihara-style plates to screen for protanopia, protanomaly, deuteranopia, and deuteranomaly.
Quick Answer
A red-green colorblind test checks whether reds, greens, oranges, and related colors are being confused. Missing several Ishihara-style plates can suggest a protan or deutan color vision deficiency, but a clinical test is needed for exact classification.
At a Glance
- Screens the most common color blindness family
- Uses Ishihara-style number plates
- Takes about 2 to 3 minutes
- Gives instant screening results
Before you start
- 1Turn off color filters, night mode, and unusual display profiles if possible.
- 2Use a normal viewing distance and avoid glare on the screen.
- 3Enter the number you see, or choose that you do not see anything.
- 4Use the blue-yellow test separately if you want a broader screening.
Take the Red-Green Colorblind Test
Answer each Ishihara-style plate below. This focused test checks the red-green confusion axis only.
Before you begin
Set up your screen and lighting
Display conditions can materially change an online color vision result. Take a moment to check these items before starting.
- Use a color screen at its normal brightness, viewed straight on.
- Turn off Night Shift, blue-light filters, grayscale, and color filters.
- Use neutral room lighting and avoid glare on the display.
- Wear your usual prescription glasses or contacts, if applicable.
- Use your first impression and answer each plate within about 5 seconds.
How to Interpret Results
Online color vision results are most useful when you look at the pattern, not just a single answer.
Most plates correct
Suggests typical red-green discrimination on this screening.
Several plates missed
May suggest a red-green color vision deficiency such as protan or deutan deficiency.
Mixed or uncertain answers
Retake under better conditions or use a professional test for a clearer answer.
What red-green colorblindness includes
Red-green colorblindness includes protanopia and protanomaly, which affect red-sensitive cone signals, plus deuteranopia and deuteranomaly, which affect green-sensitive cone signals. These conditions are inherited most often and are much more common in men than women.
Why Ishihara-style plates are used
Ishihara-style plates use dots of different hues and similar brightness to hide a number. People with normal red-green discrimination can usually read the number. People with red-green deficiency may see a different number or no number at all.
Frequently Asked Questions
Can this tell me whether I have protanopia or deuteranopia?
Not definitively. Ishihara-style plates can flag red-green deficiency, but an anomaloscope or professional color vision test is needed to classify the exact subtype.
Does a red-green test also check blue-yellow color blindness?
No. Red-green plates do not screen for tritanopia or tritanomaly. Use the blue-yellow test or the full combined test for broader screening.
Why is red-green colorblindness so common?
The genes for red and green cone opsins are on the X chromosome, so inherited red-green color vision deficiency is much more common in males.