Interactive tool
Color blindness simulator
Load an image and see it through different types of color blindness, alone or combined, with an intensity setting for each filter, or turn on the camera to see your surroundings live.
Drag an image here
JPG, PNG, WebP, GIF
External image: downloading the results may be blocked by the browser if the source server doesn't allow requests from other domains. Importing a file directly is preferable.
Color blindness filters
On mobile, the rear camera is used by default.
The 4 types of color blindness simulated
Each filter matches an affected type of retinal cone. The mechanism behind each one is explained in our article on the types of color blindness.
Protanomaly / Protanopia
Reduced or absent sensitivity to long wavelengths: reds look darker and get confused with green.
Deuteranomaly / Deuteranopia
The most common form of color blindness: red and green get confused, without the red looking darker.
Tritanomaly / Tritanopia
Rare: blue and yellow become hard to tell apart.
Achromatomaly / Achromatopsia
Very rare: vision in shades of gray, with no color discrimination.
Before using the simulator
Are my images sent to a server?
No. All the processing, whether from a file, a URL or the camera, happens locally in your browser (Canvas and WebGL). No image is uploaded or stored anywhere other than on your device.
Can I use the live camera?
Yes. Camera mode applies the filters in real time on the video feed, which is useful to see the effect on your surroundings right away rather than on a photo.
What is the simulation based on?
On the color transformation matrices published by Machado, Oliveira and Fernandes (2009), the most cited academic reference for this kind of simulation. The intensity is adjustable because most forms of color blindness are partial anomalies (-omaly), not total absences (-opia).
What's the difference with the Ishihara test?
The Ishihara test measures your own color vision. This simulator does the opposite: it shows you what a color blind person would see, from an image of your choice.