Color blindness (color vision deficiency) affects roughly 1 in 12 men and 1 in 200 women worldwide, yet many people are unaware they have it. This free simulated Ishihara-style test presents 12 dot plates — each hiding a number visible only to people with normal color vision. Your responses identify whether you show signs of red-green deficiency (protan or deutan) or blue-yellow deficiency (tritan).
Color Vision Screening
Plate 1 of 12What number do you see in the circle below?
Your Score
correct out of 12
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Plate-by-Plate Breakdown
What Your Results Mean
Important Disclaimer
This is a simulated screening tool, not a certified clinical Ishihara test. Dot plates are generated algorithmically. Monitor calibration, screen brightness, and ambient lighting can affect results. This tool cannot diagnose color vision deficiency. For an accurate diagnosis, please consult a licensed optometrist or ophthalmologist.
How to Use the Color Blindness Test
This free color blindness test uses 12 simulated Ishihara-style dot plates to screen for the most common types of color vision deficiency. Each plate hides a number inside a field of colored dots — people with normal color vision can read the number easily, while those with certain deficiencies cannot distinguish the foreground dots from the background. The entire test takes under 2 minutes.
Step 1: View Each Plate Carefully
Each plate shows a circular field of dots. Look at it for 3–5 seconds in normal lighting conditions. Avoid squinting or zooming in excessively — the test is designed to be viewed at normal screen distance. If you cannot see a number after 5 seconds, use the "I can't see a number" button rather than guessing.
Step 2: Select Your Answer
Tap or click the number you see. You can also tap "I can't see a number" if the dots appear to all be the same color. The first two plates are demo plates that everyone should be able to read — they confirm the test is displaying correctly on your screen. Answer all 12 plates, then click "See Results."
Step 3: Read Your Color Blindness Screening Result
Your result shows a score out of 12, a severity classification, and the most likely type of color vision deficiency indicated by your missed plates. Plates 3–6 target red-green deficiency (the most common type), plates 7–9 target blue-yellow deficiency (tritanopia), and plates 10–12 assess severity across both channels. A plate-by-plate breakdown lets you see exactly which plates you missed.
Understanding the Types of Color Blindness
There are three main categories of color vision deficiency tested here:
- Protanopia / Protanomaly (red-weak): Red-sensitive cones are absent or reduced. Reds appear dark and are confused with browns and greens. Affects about 1% of males.
- Deuteranopia / Deuteranomaly (green-weak): Green-sensitive cones are absent or reduced. The most common type, affecting about 5–8% of males. Greens and reds are easily confused.
- Tritanopia / Tritanomaly (blue-yellow): Blue-sensitive cones are affected. Blues look greenish and yellows appear pinkish or white. Much rarer — affects about 1 in 10,000 people.
Tips for Accurate Results
For best results, take the test in a well-lit room (not in bright sunlight or darkness), set your screen to full brightness, and remove tinted glasses or contacts. The color blindness test is calibrated for standard sRGB screens. Results on screens with extreme color profiles may not accurately reflect your true vision. If you suspect a deficiency based on these results, book an appointment with an optometrist for an official diagnosis.
Frequently Asked Questions
Is this color blindness test free?
Yes, the test is completely free with no signup, account, or payment required. Open the page and start immediately.
Is my data safe and private?
Yes. The entire test runs locally in your browser. Your answers are never sent to any server or stored anywhere — all scoring happens on your device.
Can this test replace a professional eye exam?
No. This is a simulation for informational and entertainment purposes only. The plates are generated programmatically, not the certified clinical Ishihara plates. For a definitive diagnosis of color vision deficiency, please consult a licensed optometrist or ophthalmologist.
What types of color blindness does this test detect?
The test screens for the three most common types: Protanopia/Protanomaly (red-weak, difficulty distinguishing red), Deuteranopia/Deuteranomaly (green-weak, most common form), and Tritanopia/Tritanomaly (blue-yellow deficiency, rarer). It does not test for achromatopsia (total color blindness).
How does an Ishihara-style color plate work?
Each plate shows a circular field filled with hundreds of colored dots. The dots form two groups: background dots and number-forming dots. The two groups differ in color but are designed to look identical in brightness. People with normal color vision can distinguish the colors and read the number. People with color deficiencies see all dots as the same color and cannot distinguish the number.
What is deuteranopia vs protanopia?
Both are forms of red-green color blindness. Protanopia means the eye lacks red-sensitive cones, making reds appear dark and hard to distinguish from browns and greens. Deuteranopia means the eye lacks green-sensitive cones — it is the most common type, affecting about 5-8% of males. People with either type often pass undetected for years.
How accurate is this online color blindness screening?
The simulated plates are designed to replicate the concept of clinical Ishihara plates using algorithmic dot generation. They can indicate a likely deficiency but are not calibrated clinical instruments. Monitor calibration, screen brightness, and ambient lighting can all affect results. Treat the outcome as a helpful screening indicator, not a diagnosis.
What percentage of people are color blind?
Approximately 8% of males and 0.5% of females have some form of color vision deficiency. Red-green deficiencies (protan and deutan) are by far the most common, affecting about 1 in 12 men. Blue-yellow deficiency (tritan) affects roughly 1 in 10,000 people of either sex.