Color Blindness Simulator - See Images as Protanopia, Deuteranopia, Tritanopia
Color Blindness Simulator
See how your pictures and colours look with each type of colour vision deficiency
Drag & drop a picture here, or click to choose
100% means the colour is missing entirely (-opia). Lower values are a weaker form (-anomaly), as in most colour blind people.
Add a picture to see how it looks with each type of colour blindness.
Check a single colour
Four Types Side by Side
Your picture is shown as it would look with missing red cones, green cones or blue cones, and with no colour at all, next to the original.
Mild to Complete
Most people with colour blindness are not fully blind to a colour. The severity slider moves from normal vision to complete loss.
A Published Model
It uses the physiologically based matrices of Machado, Oliveira and Fernandes (2009), applied in linear light, a model widely used in accessibility research.
Nothing Is Uploaded
The simulation runs on your device, so you can check unreleased designs and screenshots safely.
Designing for Colour Blindness
About 1 in 12 men and 1 in 200 women have some form of colour vision deficiency, most often a weak or missing response to red or green light. They do not see in black and white; they confuse colours that differ mainly in how red or green they are, such as red and green, brown and orange, or blue and purple. A chart that relies on red versus green to carry its meaning, or a status light that is only ever red or green, can be unreadable to them.
Use this page to test designs, not to diagnose anyone. Simulations are an approximation: real vision varies between people, and a screen, its brightness and the room all change what is seen. The surest fix is not to depend on colour alone: add labels, patterns, icons or different brightness levels, and keep good contrast between foreground and background. If two things you need to tell apart look the same in the simulation, change them until they do not.
Key Takeaways
- Model: Machado et al. 2009, in linear RGB; results match the reference implementation to within one colour level.
- Single colours: Pick any colour to see its four simulated versions and their hex codes.
- Related tools: See also the Color Contrast Checker and the Image Color Palette Extractor.