Deuteranopia Color Blindness Simulator
FreeSee how your colors look to users with deuteranopia (red-green color blindness). Upload an image or enter a color. Free, browser-based.
What's next
Settings guide
Types of red-green color blindness:
| Condition | Severity | Prevalence (male) | What changes |
|---|---|---|---|
| Deuteranomaly | Mild–moderate | 5% | M-cones present but shifted — reduced green sensitivity |
| Deuteranopia | Severe | 1% | M-cones absent — red and green both appear as yellow-brown |
| Protanomaly | Mild–moderate | 1% | L-cones shifted — reduced red sensitivity |
| Protanopia | Severe | 1% | L-cones absent — red appears very dark; more severe than deuteranopia |
Designing for red-green color blindness:
- ·Never use red/green as the only differentiator for status, success/error, or chart series
- ·Add shape, icon, or text labels alongside color coding — a ✓ and ✗ alongside green and red
- ·Use blue/orange instead of green/red for complementary data — deuteranopes perceive this pair distinctly
- ·Check your chart colors: if two data lines merge into the same color in the simulation, redesign
Safe color pairs for data visualization:
- ·Blue (#1A73E8) vs Orange (#FA7B17) — distinct for all color blindness types
- ·Purple vs Green — distinct for red-green color blindness
- ·Avoid: Red vs Green, Brown vs Olive, Blue-Green vs Gray
Format comparison
Deuteranopia vs protanopia: Both are red-green color blindness but affect different cone types. Deuteranopia (absent M-cone) makes red and green appear as brownish-yellow. Protanopia (absent L-cone) similarly confuses red and green, but additionally makes red appear very dark — almost black in severe cases. Protanopia has a larger impact on red hues; deuteranopia has a larger impact on green hues.
Deuteranopia vs tritanopia: Tritanopia is blue-yellow color blindness (absent S-cone), affecting about 0.001% of the population — extremely rare. Blue appears green; yellow appears violet or gray. Tritanopia is far less common than red-green types and requires separate design consideration.
Color blindness simulation vs real experience: The simulation approximates the perceptual experience using published mathematical models. Real perception varies between individuals — even people with the same diagnosis experience it differently. Use simulation as a starting point for design decisions, then validate with users who have color vision deficiencies when possible.
How it works
Upload or enter color
Drop an image file to simulate how the whole image appears, or enter a single color value to see its deuteranopia equivalent.
Apply simulation
A color matrix transformation is applied using the Machado 2009 model, processing colors in linearized RGB space.
Compare
View original and simulated side-by-side. Identify color pairs that become indistinct in the simulation.
About this format
Deuteranopia is the most common form of color blindness, affecting approximately 1 in 12 men and 1 in 200 women globally — around 8% of the male population. People with deuteranopia have absent or non-functional M-cones (medium-wavelength cones), which process green light. The result: they cannot distinguish red from green, and instead perceive them both as shades of yellow and brown.
For interface designers, deuteranopia has a direct consequence: any design that uses green to mean "success" and red to mean "error" — without any additional differentiator — will be ambiguous or invisible to 1 in 12 of your male users. Traffic light patterns (green/red status indicators), charts that use red and green as contrasting data series, and form validation that relies on color alone all fail this test.
This simulator applies a color matrix transformation based on the Machado, Oliveira & Fernandes (2009) model, which produces scientifically validated approximations of how colors appear to people with deuteranopia. Upload an image or enter a color to see the simulated view — then use it to make informed decisions about color-based information encoding.