Colour Blindness Simulator
Upload any image to see how it appears to users with different types of colour vision deficiency. Essential for WCAG 1.4.1 (Use of Colour).
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WCAG 1.4.1 — Use of Colour
Colour must not be the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. Use shape, pattern, or text labels alongside colour.
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Every export includes a legal-evidence metadata footer with the audit ID, generation date, tool version, EN 301 549 clauses, and the standard disclaimer. Legal-grade evidence — not legal advice.
Simulation method
Colour vision deficiency simulations use colour transformation matrices based on the Viénot, Brettel, and Mollon (1999) simplified model. Results are perceptually representative for design review purposes but may differ from higher-precision spectral models (e.g. Machado et al. 2009). Use for design review and accessibility checking — not clinical diagnosis.