What do colorblind people see?
Quick Answer
Most colorblind people do see color, just not all the differences other people see. The most common type, red-green color blindness, makes reds, greens, browns and oranges look alike. Seeing only in shades of gray (complete color blindness) is very rare.
Key Takeaways
- About 1 in 12 men and 1 in 200 women (of Northern European ancestry) have color vision deficiency
- Red-green deficiency is by far the most common type
- Deuteranomaly (reduced green sensitivity) is the single most common form
- Blue-yellow (tritan) deficiency is rare and affects men and women equally
- True total color blindness (monochromacy) is very rare
- Most inherited color blindness is present from birth and does not get worse
How Color Vision Works
The retina has three types of cone cells, each most sensitive to long (red), medium (green) or short (blue) wavelengths of light. The brain compares the signals from the three types to produce every color you see. Color blindness happens when one type of cone is missing or works differently.
Types of Color Blindness and What They Look Like
| Type | What is affected | What the person sees |
|---|---|---|
| Deuteranomaly | Green cones shifted | Greens look more red; yellow and green, red and brown are easy to confuse. Mild to strong. |
| Deuteranopia | No working green cones | Reds, greens, oranges and browns collapse into similar yellowish-brown tones. |
| Protanomaly / protanopia | Red cones shifted or missing | Similar red-green confusion, and reds look darker; a red traffic light can look dim. |
| Tritanomaly / tritanopia | Blue cones affected | Blue and green, and yellow and pink/violet, are confused. Rare. |
| Blue cone monochromacy | Only blue cones and rods work | Very limited color, often with poor acuity and light sensitivity. Very rare. |
| Achromatopsia (rod monochromacy) | No working cones | Only shades of gray, poor sharpness and strong sensitivity to light. About 1 in 30,000 people. |
How Common Is Color Blindness?
Red-green color blindness is inherited on the X chromosome. Men have one X chromosome, so a single affected gene is enough; women need it on both. That is why roughly 8% of men and 0.5% of women of Northern European ancestry have red-green deficiency, with lower rates in many other populations.
Color vision problems can also be acquired later in life from eye diseases (such as glaucoma or macular degeneration), some medications and optic nerve damage. Acquired changes often affect blue-yellow perception and can change over time, so they should be checked by a doctor.
Everyday Challenges
- Telling ripe from unripe fruit, or rare from cooked meat
- Reading color-coded charts, maps and wiring
- Choosing matching clothes
- Status lights on devices (red vs. green LEDs)
- Traffic lights: most people learn the position (red top, green bottom) rather than relying on color
Do Color Blind Glasses Work?
Tinted "color blind glasses" filter overlapping wavelengths to increase contrast between some reds and greens. Some people with mild to moderate red-green deficiency find colors more distinct while wearing them, but they do not restore normal color vision and do not help everyone. Color blindness from inherited cone defects has no cure today.
Frequently Asked Questions
Do colorblind people see in black and white?
Almost never. Seeing only grays (achromatopsia) is very rare. The vast majority of colorblind people see many colors but confuse certain shades.
What color is hardest for colorblind people to see?
For the common red-green types, distinguishing red from green (and related shades like brown, orange and olive) is hardest. For tritan types, blue versus green and yellow versus pink are hardest.
Can women be colorblind?
Yes, but red-green color blindness is much less common in women (about 1 in 200 among people of Northern European ancestry) because it requires the gene on both X chromosomes.
How do I know if I am colorblind?
Screening tests like the Ishihara plates (numbers hidden in colored dots) can flag red-green deficiency. An eye doctor can confirm the type and severity with further tests.
Can color blindness be cured?
Inherited color blindness cannot currently be cured. Gene therapy has worked in animal studies and early trials target rare forms such as achromatopsia, but it is not an available treatment.