Test how your images and designs appear to people with different types of color vision deficiency including protanopia, deuteranopia, tritanopia, and more
Roughly 1 in 12 men and 1 in 200 women experience some form of color vision deficiency. If you design interfaces, marketing materials, or any visual content, there is a real chance a meaningful segment of your audience sees your work differently than you intend. This simulator lets you upload any image and instantly preview how it looks under protanopia, deuteranopia, tritanopia, and achromatopsia. Side-by-side comparison makes it straightforward to spot problem areas where color alone carries meaning. Test early, test often, and ship designs that work for everyone.
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Professional color grading: adjust brightness, contrast, saturation, hue, shadows, highlights, and temperature. Create cinematic looks with color curves.
Extract dominant, vibrant, or muted colors from images. Generate color schemes with HEX, RGB, HSL values and export palettes for design projects.
Crop and trim images with precision visual selection. Features aspect ratio presets (1:1, 16:9, 4:3), free-form cropping, grid overlays, and pixel-perfect adjustments for professional results.
Before shipping a status dashboard, you need to know whether the red/green health indicators are distinguishable to colour-blind users.
Input
dashboard.png · simulate Deuteranopia
Result
A re-rendered preview where the red and green dots collapse to near-identical olive, failing.
The simulator transforms the image through a scientifically modelled colour-vision deficiency, so you see what a red-green colour-blind user sees (red-green deficiency affects roughly 1 in 12 men). When red and green become indistinguishable here, it is concrete proof you need shape or text labels, not just colour.
Roughly 1 in 12 men and 1 in 200 women experience some form of color vision deficiency. If you design interfaces, marketing materials, or any visual content, there is a real chance a meaningful segment of your audience sees your work differently than you intend. This simulator lets you upload any image and instantly preview how it looks under protanopia, deuteranopia, tritanopia, and achromatopsia. Side-by-side comparison makes it straightforward to spot problem areas where color alone carries meaning. Test early, test often, and ship designs that work for everyone.
Check UI mockups and web designs to verify that color is never the sole carrier of information.
Systematically verify designs against accessibility standards before release.
Ensure charts, graphs, and heatmaps remain readable under all vision conditions.
Confirm that your brand colors remain distinguishable across all deficiency types.
Show colleagues firsthand how users with color deficiency experience your product.
The simulator applies transformation matrices to each pixel, modeling how reduced or absent cone-cell responses alter perceived color. Protanopia and deuteranopia (red-blind and green-blind) are the most common forms, together accounting for roughly 99% of color vision deficiency cases. Tritanopia affects blue-yellow perception and is far rarer. Achromatopsia removes all color perception entirely. Because the processing runs in-browser via canvas operations, your images are never uploaded to any server.
Start with deuteranopia, it is the most common form, affecting about 6% of males. Then move through protanopia and tritanopia for full coverage.
No. The simulation is rendered in real-time on a canvas element. Your uploaded file stays untouched.
Absolutely. Take a screenshot, upload it, and cycle through each simulation type. It is one of the quickest ways to audit a live interface.
They use established color transformation matrices from vision science research. While individual perception varies, they give a reliable approximation of how most affected users see color.
Images are decoded, edited, and exported entirely inside this browser tab. No originals, exports, or metadata are uploaded.