Color Blindness Simulator
Experience how the world looks with different types of color vision deficiency. Upload images or use your webcam to simulate color blindness in real-time.
Vision Type
Color enhancement
Upload Image
Upload an image to simulate how it appears with color blindness
Drag and drop your image here
or
Supports JPG, PNG, GIF, WebP
Basics
What is a Color Blindness Simulator?
A color blindness simulator is an essential tool that demonstrates how individuals with color vision deficiencies perceive the world. Color blindness, also known as color vision deficiency, affects approximately 8% of men and 0.5% of women worldwide. This condition makes it challenging to distinguish between certain colors, particularly red and green combinations. Our simulator helps designers, developers, and educators understand these visual differences to create more accessible and inclusive content.
The simulator works by applying scientifically accurate color transformation algorithms to images or live video streams. When you upload an image or activate your webcam, our tool processes each pixel to replicate how someone with protanopia, deuteranopia, tritanopia, or achromatopsia would see that content. Use the slider comparison for quick before-and-after checks, or switch to side-by-side mode to view both versions simultaneously. This real-time simulation provides immediate feedback, making it invaluable for testing website designs, graphics, presentations, and any visual content that needs to be accessible to people with color vision deficiencies.
How it works
How Image Simulation Works
Our image simulation feature uses the Machado et al. physiologically-based model to transform your uploaded images. When you drag and drop an image or select one from your device, the simulator converts the color space from RGB to LMS (Long, Medium, Short wavelength), applies the appropriate color vision deficiency matrix, and converts back to RGB. This process accurately replicates the biological mechanisms of color blindness. The before-and-after comparison slider lets you instantly see the difference between normal color vision and simulated color blindness, helping you identify potential accessibility issues in your designs.
How it works
How Webcam Simulation Helps Designers
The live webcam simulation feature is a game-changer for designers and developers who need to test real-world scenarios. By pointing your camera at printed materials, screens, product packaging, or environmental signage, you can instantly see how people with color blindness would perceive these items. This is particularly valuable for user interface designers who want to test color combinations in real-time, educators creating visual learning materials, and product designers ensuring their packaging is accessible. The webcam mode processes video at high frame rates, providing smooth, real-time feedback that helps you make instant design decisions without the need for multiple test prints or iterations.
Reference
The Eight Vision Types, and What Each One Loses
Every mode in the dropdown corresponds to a specific cone photoreceptor being missing, shifted, or absent altogether. Knowing which is which tells you what to look for.
Normal color vision is trichromatic: three cone types, sensitive to long (L), medium (M), and short (S) wavelengths. Color vision deficiency happens when one of those channels is gone — the -anopia conditions — or present but shifted along the spectrum, the -anomaly conditions. The anomalous forms are milder and far more common, which is why severity is a slider here and not a checkbox.
| Type | Cone affected | What becomes hard to tell apart | Roughly how common |
|---|---|---|---|
| Deuteranomaly | M-cone shifted | Greens and reds drift toward each other; the mildest and most familiar form. | About 5% of men — the most common of all |
| Deuteranopia | M-cone absent | Red, green, orange, and brown collapse into a narrow yellow-to-beige band. | About 1% of men |
| Protanomaly | L-cone shifted | Similar confusions to deuteranomaly, with reds looking somewhat dimmer. | About 1% of men |
| Protanopia | L-cone absent | Same red-green collapse, but reds also lose brightness — dark red can read as black. | About 1% of men |
| Tritanomaly | S-cone shifted | Blue and green, plus yellow and pink, become harder to separate. | Very rare |
| Tritanopia | S-cone absent | The blue-yellow axis goes; blues turn greenish and yellows wash toward pale grey. | Very rare, and affects men and women about equally |
| Achromatopsia | No functioning cone channels | All hue information, leaving lightness alone. Often comes with light sensitivity and low acuity. | Roughly 1 in 30,000 |
| Normal vision | None | Nothing — included as the baseline for side-by-side comparison. | — |
Why this tool
Why Use Our Color Blindness Simulator?
Accessibility Testing
Ensure your designs are accessible to over 300 million people worldwide with color vision deficiencies. Test images and live content instantly.
Dual Mode Testing
Choose between image upload mode for testing static designs or webcam mode for real-time simulation of physical materials and screens.
Real-time Results
Get instant feedback with GPU-accelerated processing. Switch between different types of color blindness and see changes immediately.
8 Vision Types
Simulate protanopia, protanomaly, deuteranopia, deuteranomaly, tritanopia, tritanomaly, and achromatopsia with adjustable severity.
Browser-Based
No installation required. Works on desktop and mobile devices. Your images are processed locally for complete privacy.
100% Free
Access all features including image simulation, webcam mode, and daltonization completely free with no registration required.
Practice
Tips for Using the Color Blindness Simulator
- Use the Image Mode to test website screenshots, logos, infographics, and marketing materials by uploading them directly.
- Try Webcam Mode to test physical products, printed materials, or existing displays in real-time without taking photos.
- Test multiple vision types including protanopia and deuteranopia, which are the most common forms of color blindness.
- Adjust the severity slider to test both complete and partial color vision deficiencies for comprehensive accessibility testing.
- Enable daltonization to see color correction techniques that can make images more distinguishable for color blind users.
FAQ
Frequently Asked Questions
What types of color blindness can I simulate?
Our simulator supports 8 types: protanopia, protanomaly, deuteranopia, deuteranomaly, tritanopia, tritanomaly, achromatopsia, and normal vision. You can adjust severity levels for each type.
Is my uploaded image saved or stored?
No. All image processing happens locally in your browser. Your images are never uploaded to our servers, ensuring complete privacy and security.
Does the webcam mode work on mobile devices?
Yes! The webcam mode works on both desktop and mobile devices. On mobile, it will use your rear camera by default, perfect for testing real-world materials.
What is daltonization?
Daltonization is a color correction technique that enhances color differences to make images more distinguishable for people with color vision deficiencies. Toggle it on to see the effect.
Can I download the simulated images?
Yes! In image mode, you can download the simulated version after processing. This is useful for sharing results with your team or including in accessibility reports.
Does daltonization actually fix an image for a color blind viewer?
It helps, but it isn’t a cure, and it’s worth understanding why. Daltonization can’t restore information a missing cone never received — what it does is redistribute the differences that would be lost into channels the viewer can still see, so hues that used to collapse become separable. The trade-off is that colors shift away from their true values, which is why a daltonized image can look strange to someone with typical color vision. It’s an assistive filter, not a correction.
Why doesn’t the simulation look like what I expected?
The most common surprise is that deuteranopia doesn’t turn red into grey — it turns red and green into similar yellowish-browns, so a red-on-green design becomes low-contrast mush rather than obviously broken. The other frequent surprise is how little changes on a well-designed page, which is the point: if your layout also uses position, shape, labels, and lightness, removing hue costs you very little.
Should I design for achromatopsia to be safe?
It’s a useful stress test but a poor design target. Complete achromatopsia is exceptionally rare — on the order of 1 in 30,000 — and optimizing for it means abandoning color as a design tool entirely. A more productive habit is to check the greyscale view for lightness contrast, then use deuteranomaly and tritanopia for the decisions that actually affect a meaningful number of users.
How accurate is the underlying model?
Image mode uses the Machado et al. physiologically-based model, which simulates anomalous trichromacy by shifting a cone’s response curve rather than deleting the channel — that’s what makes the severity slider meaningful rather than cosmetic. It’s a well-regarded model, but any simulation is an approximation of an average observer. Two people with the same diagnosis can differ noticeably, so use it to find risky color pairs, not to predict one individual’s experience.