Colour Blindness Simulator
Simulate how colours appear to people with colour blindness. Deuteranopia, protanopia, tritanopia and achromatopsia. Free.
How to use the Colour Blindness
Types of colour blindness
Deuteranopia (red-green, no working green cones) affects about 1% of males, and its milder form, deuteranomaly, about 5%. Protanopia (red-green, no working red cones) affects about 1% of males. Tritanopia (blue-yellow) is rare. Achromatopsia (complete colour blindness) is very rare. Together, some form of colour blindness affects roughly 1 in 12 men and 1 in 200 women.
Designing for accessibility
Never rely on colour alone to convey information. Use patterns, icons or labels alongside colour. Check that text has sufficient contrast under all simulations. The WCAG 2.1 AA standard requires 4.5:1 contrast ratio for normal text.
Frequently asked questions
Is the Colour Blindness free to use?
Yes, the Colour Blindness is completely free. There is no sign-up, no account required, and no limit on how often you can use it.
What colour formats does the Colour Blindness support?
The Colour Blindness works with HEX, RGB and HSL colour formats. You can convert between them and copy any value with one click.
What devices does the Colour Blindness work on?
The Colour Blindness works on any device with a modern web browser — desktop, laptop, tablet, or phone. It is mobile-friendly and works offline once the page has loaded.