What this tool is for
Colour blindness simulator
Preview a colour under common vision deficiencies. The aim is a useful result without making you learn a full piece of software first.
Free · No sign-up · PrivateColour & Accessibility
See this image through a colour-blindness simulation.
Preview approximate deuteranopia, protanopia or tritanopia transformations locally.
1 Choose2 Adjust3 Preview & download
Before you finish
A quick check makes a better result.
OutMonkey is built to be simple enough for someone doing this once and useful enough for someone who does it every day.
Good to know
Use the number, then use your eyes.
A passing contrast result is useful, but also look at the real text size, weight, background and surrounding colours. Readability is the goal, not just the score.
If the result is for someone else, open it once as they would see it. That simple check catches a surprising number of tiny mistakes.
In plain English
You do not need to be an expert.
You do not need to be a designer to use these checks. If text feels faint or difficult to read, choose a clearer combination even when the numbers are technically acceptable.
Use contrast checks as a floor for readability, not the whole accessibility story.