Color Blindness Simulator

Key features

• Eight vision types: normal, protanopia/protanomaly, deuteranopia/deuteranomaly, tritanopia/tritanomaly and achromatopsia.
• Severity slider (0–100%) for the three anomaly types; the dichromacy types render at full strength.
• Starts with a built-in test scene — gradient stripes plus the classic red/green and blue/yellow tells — no upload required.
• Drop in your own PNG, JPG or WEBP to simulate a design or photo instead.
• Side-by-side original vs simulated canvases for instant comparison.
• Exports the simulated image as a PNG at the source's full resolution.

How it works

1. 1

   Choose an image

   The tool opens with a vivid procedural test scene. Drag in your own image any time to replace it.

2. 2

   Pick a deficiency

   Tap one of the eight type buttons; each explains in one line what it hides or shifts.

3. 3

   Tune severity

   For the anomaly (weak) types, slide from a subtle 10% hint of the deficiency to the full 100% condition.

4. 4

   Compare and export

   Read the two canvases side by side, then download the simulated version as a full-resolution PNG.

Tips for better results

• 💡The red/green circle pair in the test scene is the fastest tell for protan and deutan deficiencies.
• 💡Screenshot your UI and simulate it — the most common failure is red/green status indicators becoming indistinguishable.
• 💡The preview is computed on a downscaled canvas (at most 640px on the long edge) to keep the slider snappy; downloads always re-render at full size.
• 💡Deuteranomaly is the most common deficiency (roughly 5% of men), so start there when auditing designs.
• 💡Pair this with the Contrast Checker — simulating vision and checking contrast catch different classes of problems.

Frequently asked questions