Accessibility
Color Blindness Simulator
See how a palette appears under different forms of color vision deficiency. Identify where colors become hard to distinguish — then test contrast with the Contrast Checker or run a full Accessibility Audit.
Designing for how color is seen
Beyond contrast ratios
The Contrast Checker tells you whether text is readable. Color blindness simulation tells you something different — whether your palette's colors remain distinguishable from each other. Two colors can both have great contrast against white while looking nearly identical to someone with deuteranopia. Both checks matter.
What the simulations show
This tool applies established color transformation matrices to approximate how colors shift under different types of color vision deficiency. Protanopia and deuteranopia (red-green deficiencies) affect roughly 8% of males. Tritanopia (blue-yellow) and achromatopsia (total color loss) are rarer but worth understanding. The simulations are approximations — individual perception varies — but they reveal the most common problem areas.
What to look for
Watch for colors that collapse into the same perceived tone. If two distinct colors become hard to tell apart, any interface element that relies on that distinction — status indicators, chart series, navigation states — may fail for affected users. Palettes from high contrast or UI design collections tend to perform better.
Practical responses
You don't need to redesign your entire palette. Common approaches include adding secondary visual cues (icons, patterns, labels), increasing lightness variation between similar hues, and reserving the most distinct pairings for the most important distinctions. A palette that works well under simulation usually works well for everyone.
Part of an accessibility workflow
This simulator works alongside Huelib's other accessibility tools. Use the Contrast Checker to verify pairwise readability. Run the Accessibility Audit to evaluate every pairing at once. Then use the Visualizer to see the palette working on real layouts, or the Token Mapper to assign design roles.