Color Blind Simulator
Upload an image and apply a colorblind filter to see it the way people with different types of color blindness may see it. Great for checking designs, charts and maps. Your image stays on your device.
Tip: drag the slider on the image to compare. Images are scaled down to at most 1600 px for speed.
Simulated types and severity
| Filter | Simulates | Colors that get confused |
|---|---|---|
| Deuteranopia / deuteranomaly | Missing or weak green-sensitive (M) cones | Reds, greens, browns and oranges |
| Protanopia / protanomaly | Missing or weak red-sensitive (L) cones | Reds, greens and browns; reds also look darker |
| Tritanopia / tritanomaly | Missing or weak blue-sensitive (S) cones | Blue with green, yellow with pink or light grey |
| Achromatopsia | No working cones, vision without color | All colors, leaving only light and dark |
The severity slider sets how strong the deficiency is. 100% shows the full “-opia” form, such as protanopia or deuteranopia. Lower values approximate the milder “-anomaly” forms, such asdeuteranomaly, the most common type. Read more inwhat colorblind people see.
How accurate is the simulation?
The simulator uses the physiologically based model published by Machado, Oliveira and Fernandes (2009), a widely used method in color science. It predicts which colors collapse together for each cone deficiency. Two things limit it: your own screen isn’t calibrated, and no image can show the inner experience of another person. Use it to find colors that become hard to tell apart, not as an exact picture.
Design checklist for color blind users
- Never rely on color alone. Add labels, icons, patterns or line styles to charts, maps and status messages.
- Avoid red-versus-green pairs for meaning such as good/bad or on/off. Blue and orange are easier to tell apart.
- Keep a clear difference in lightness between colors that must be told apart, not just a difference in hue.
- Label chart lines directly instead of relying on a color legend.
- Check every important screen in the deuteranopia and protanopia filters, then in tritanopia.
Looking for a filter for your own screen?
If you’re color blind and want your device to make colors easier to tell apart, most systems have a built-in color filter. These shift colors to separate them more; they don’t restore color vision.
- Windows 11: Settings › Accessibility › Color filters.
- macOS: System Settings › Accessibility › Display › Color filters.
- iPhone and iPad: Settings › Accessibility › Display & Text Size › Color Filters.
- Android: Settings › Accessibility › Color correction (the exact path varies by phone).
Who is this for?
- Designers and developers checking that charts, UI states and maps work without relying on color alone.
- Teachers and parents who want to understand what a color blind child sees.
- Friends and family of someone who is color blind.
Want to know about your own color vision? Take the color blind test, or read how each of thetypes of color blindness affects what people see.
More color vision tests
Frequently asked questions
How does the color blind simulator work?
Each pixel is converted to linear RGB and transformed with the physiologically based model of Machado, Oliveira and Fernandes (2009), which estimates what a person with a given cone deficiency perceives. Lower severities blend the model with normal vision to approximate anomalous trichromacy.
Is my photo uploaded anywhere?
No. The simulation runs entirely in your browser. Your image never leaves your device.
Is the simulation exactly what color blind people see?
No simulation can show exactly what another person experiences, and your own screen and eyes add their own differences. The simulator shows which colors become hard to tell apart, which is what matters for design and understanding.
What is the difference between a color blind simulator and a color blind filter?
A simulator, like this one, changes an image to show how it may look to someone with color blindness, so people with typical vision can check it. A filter for color blind people does the opposite job: it shifts screen colors so that hard-to-tell colors become easier to separate. Both are often called “colorblind filters”.
What is daltonization?
Daltonization recolors an image so that information lost to a color vision deficiency is moved into colors the viewer can still tell apart. It can help in some cases but can’t restore normal color vision. This simulator doesn’t daltonize; it only shows the problem so you can fix the design itself.