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Achromatopsia Simulator

See your website in complete grayscale with our achromatopsia simulator. Total color blindness affects 1 in 30,000 people — but designing for it benefits everyone. If your interface works in black and white, it works for every user.

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Achromatopsia

Total color blindness

Achromatopsia (total color blindness) affects approximately 1 in 30,000 people. Individuals see the world entirely in grayscale — no color perception at all. This makes it the ultimate test for accessible design: if your interface works in black and white, it works for everyone. Rely on contrast, typography, spacing, and icons rather than color to communicate information.

Achromatopsia

Total color blindness

Normal Vision

Trichromatic — all three cone types

Deuteranopia

Green-blind (~6% of males)

Protanopia

Red-blind (~2% of males)

Tritanopia

Blue-blind (rare)

Frequently Asked Questions

What is achromatopsia?
Achromatopsia (also called total color blindness or rod monochromacy) is a condition where all three cone cell types are non-functional, resulting in complete grayscale vision. It affects approximately 1 in 30,000 people. Individuals with achromatopsia see the world entirely in shades of gray, similar to a black-and-white photograph.
Why is achromatopsia the ultimate accessibility test?
If your website's information is still clear in grayscale, it will be accessible to everyone — including users with any type of color blindness, low vision, or situational impairments (like bright sunlight). Testing with achromatopsia simulation reveals whether you're relying too heavily on color to communicate meaning.
Does achromatopsia mean I should avoid color in my designs?
No — color adds beauty and emotional resonance. The goal is not to eliminate color but to ensure color is never the sole means of conveying information. Use high contrast ratios, clear typography, spacing, borders, and icons alongside color. Our achromatopsia simulator helps you find the balance.
What WCAG success criteria relate to achromatopsia?
SC 1.4.1 (Use of Color) directly addresses this: 'Color is not used as the only visual means of conveying information.' SC 1.4.3 and 1.4.11 (Contrast Minimum and Non-text Contrast) also apply — when color differences are removed, contrast ratios become the primary way to distinguish elements. Aim for 4.5:1 minimum for text and 3:1 for UI components.

Related Tools

Deuteranopia SimulatorProtanopia SimulatorTritanopia SimulatorContrast Checker