Color Blindness Simulator

Load an image (no upload) and preview how it appears under common color vision deficiencies. Compare side-by-side or with a split slider, adjust severity, and export.

How to Use

  1. Click Choose Image to load a file locally (nothing is uploaded).
  2. Select a Simulation type and adjust Strength.
  3. Use Compare Mode for side-by-side, simulated-only, or split-view.
  4. Use Download to export the simulated result, or Share Link to share settings.

File support depends on your browser. Common formats (PNG/JPG/GIF/WebP/SVG/AVIF) usually work. HEIC/HEIF may require browser support or an optional decoder (not required for this tool to function).

Preview Lab
Original vs simulated rendering (client-side canvas).
Image
—
Size
—
Mode
—
Sim
—
No image loaded
Choose an image to start. Nothing is uploaded.
Note: Simulation is an approximation (matrix-based).
Inputs & Settings
Load a local image, choose a simulation, and compare views.
No upload. Your file is processed in the browser. Some formats depend on browser support.
These are common categories used for accessibility checks.
100% (0% = original, 100% = full simulation)
Split mode uses a draggable divider to reveal original vs simulated.
50%
Show Work (what the simulator does)
—
The simulator applies a color transform per pixel (matrix approximation). This is useful for accessibility previews, but it’s not a medical diagnostic.

Reference

  • Protan*: reduced/absent L-cone response (reds)
  • Deutan*: reduced/absent M-cone response (greens)
  • Tritan*: reduced/absent S-cone response (blues)
  • Achromat*: near/no color perception (grayscale-like)

For design checks, also verify text/background readability with a contrast tool.

FAQ

Does this upload my image?

No. Your image stays on your device and is processed in your browser.

What image formats are supported?

Whatever your browser can decode. PNG and JPG are universally supported. WebP/GIF/SVG are commonly supported. AVIF is supported in most modern browsers. HEIC/HEIF support varies.

Is this accurate?

It’s a practical approximation intended for accessibility previews. Real-world perception varies by individual and viewing conditions.

Can I export the simulated image?

Yes—download exports are generated from the simulated canvas (client-side).

Tool Info

Last updated:

Updates may include more simulation modes, improved browser format support, and edge-case handling.