See how your palette looks to people with different types of color vision deficiency. Enter up to 6 colors, then check each simulation row below.
Full trichromatic color vision — three functioning cone types.
Red-blind. L-cones (red) are absent. Reds appear dark; confusion between red, green, and brown.
Green-blind. M-cones (green) are absent. Most common form. Greens and reds are easily confused.
Blue-blind. S-cones (blue) are absent. Blues appear green; yellows appear violet or grey.
Complete color blindness. No functional cones — only rod-based monochromatic vision.
Color vision deficiency affects roughly 8% of men and 0.5% of women of Northern European descent. Deuteranomaly (reduced green sensitivity) is by far the most common form, followed by protanomaly (reduced red sensitivity). Tritanopia and complete achromatopsia are rare.
A palette accessible to color-blind users relies on more than hue — lightness contrast is the most robust signal. Use the Contrast Checker to verify text legibility, and avoid communicating information through color alone (use icons, labels, or patterns too).
Protanopia and deuteranopia both cause confusion between reds, greens, and browns. If your palette contains red and green together as the only distinguishing cues (e.g. status indicators), consider adding blue or ensuring strong lightness difference between them.
This simulator uses the Viénot et al. transformation matrices, which model dichromacy (complete absence of a cone type). Real-world color vision deficiency is a spectrum — many people have reduced sensitivity rather than full absence. Use this as a design sanity check, not a clinical tool.