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Open the Img Stop Color Blindness Simulator, add your image and choose protanopia, deuteranopia, tritanopia or achromatopsia, or a milder anomaly with a severity slider. Or create a side-by-side chart of all types to check your design at a glance.
About the Color Blindness Simulator
The Img Stop Color Blindness Simulator shows how an image, chart, website screenshot or design looks to people with different types of colour vision deficiency. It uses the Machado 2009 model, a widely used scientific method for simulating colour blindness.
Simulate protanopia (red-blind), deuteranopia (green-blind), tritanopia (blue-blind) and achromatopsia (no colour), plus milder protanomaly, deuteranomaly and tritanomaly with a severity slider. Make a comparison chart of every type side by side and check many images at once.
Key features
- Four main typesProtanopia, deuteranopia, tritanopia and achromatopsia.
- Milder anomaly formsProtanomaly, deuteranomaly and tritanomaly with a severity slider.
- Comparison chartAll types side by side in one image.
- Machado 2009 modelA scientific simulation model.
- Any imagePhotos, charts, maps, UI screenshots and logos.
- BulkCheck many images at once and download a ZIP.
How to use the Color Blindness Simulator
- Add images Drop a design, chart or screenshot.
- Choose a type Pick protanopia, deuteranopia, tritanopia, achromatopsia or an anomaly form.
- Set the severity For milder forms, move the severity slider.
- Compare and download View all types side by side and download.
Color Blindness Simulator at a glance
| Price | Free, no watermark |
|---|---|
| Types | Protanopia, deuteranopia, tritanopia, achromatopsia |
| Milder forms | Protanomaly, deuteranomaly, tritanomaly with severity |
| Model | Machado 2009 |
| Bulk | Yes – many images at once, ZIP download |
| Processing | In your browser – photos are not uploaded |
When to use it
- Check website and app designs for colour accessibility.
- Make sure charts and graphs are readable for colour-blind readers.
- Test maps, infographics and signage.
- Review brand colours and logos.
- Understand what colour-blind friends, students or customers see.
Tips for the best result
- Deuteranomaly is the most common type – always check it.
- If two colours look the same in the simulation, add labels, patterns or contrast.
- Use the comparison chart to review all types in one view.
- Do not rely on red versus green alone to show meaning.
Frequently asked questions
How can I see an image as a colour-blind person would?
Add it to the Img Stop Color Blindness Simulator and choose a type such as deuteranopia. The image is recoloured to show how it appears with that colour vision.
What is the difference between protanopia and deuteranopia?
Both are red-green colour blindness. Protanopia means the red-sensitive cones are missing; deuteranopia means the green-sensitive cones are missing.
What is tritanopia?
A rare form of colour blindness affecting blue-sensitive cones, which makes blue and yellow hard to tell apart.
How accurate is the simulation?
It uses the Machado 2009 model, a widely used scientific method. Real colour vision varies from person to person, so treat it as a close guide.
Is the color blindness simulator free?
Yes, it is free and your images are processed in your browser, not uploaded.
Learn more
- MDN: Image file types – common image formats explained
Made and maintained by the Img Stop team.