Color Blindness Simulator
See how your image looks to people with color vision deficiency. Simulate protanopia, deuteranopia, tritanopia, and achromatopsia with accurate color matrix transforms.
300+ images simulated
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4 Vision Types
Protanopia (red-blind), deuteranopia (green-blind), tritanopia (blue-blind), and achromatopsia (total color blindness) — covering the most common color vision deficiencies.
Two Comparison Modes
Side-by-side shows both versions at once for quick comparison. The overlay slider lets you drag a divider to see the exact difference at any point in the image.
100% Private
Color matrix transforms run entirely in your browser via the Canvas API. Your image stays on your device — no upload, no storage, no tracking.
What is color blindness simulation?
Color blindness simulation applies mathematical transforms to pixel data that model how the human visual system processes color when specific cone types are absent or dysfunctional. This tool uses Brettel/Vienot color matrices — the standard approach in accessibility research — to remap each pixel's RGB values. The result shows what a person with that specific type of color vision deficiency would perceive. Roughly 8% of men and 0.5% of women have some form of color vision deficiency, making this essential for accessible design. To extract the specific colors in your image, use the Color Picker or the Color Palette Extractor.
Types of color vision deficiency
Protanopia means the red cone cells are absent — reds appear dark and are hard to distinguish from greens and browns. Deuteranopia is the absence of green cones — green-red discrimination is lost, the most common type affecting about 6% of males. Tritanopia affects blue cones and is much rarer — blues and yellows become confused. Achromatopsia is total color blindness: the world appears in shades of gray. Testing with all four types ensures your design communicates clearly regardless of the viewer's color perception. For checking specific color pair contrast, use the Contrast Checker.
Using this for accessible design
Run your UI screenshots, infographics, charts, maps, and marketing images through each simulation type. If information is lost — text becomes invisible against its background, chart segments merge, or status indicators (red/green) become indistinguishable — your design needs adjustment. Common fixes include adding patterns or labels alongside color, using colorblind-safe palettes, and ensuring sufficient luminance contrast. To resize your designs for different platforms after testing, use the Social Media Resizer or the Image Resizer.
Side-by-side vs overlay comparison
Side-by-side mode places the original and simulated versions next to each other, making it easy to scan both at once. Overlay mode stacks them with a draggable slider — useful for spotting subtle differences in specific regions. Both modes render at the same resolution so the comparison is pixel-accurate. The simulated version can be downloaded at full original resolution. Explore all 88 image tools. Learn more in our articles on color palette extraction and color picker guide.