Preview your design through color vision deficiencies

Protanopia and protanomaly stem from missing or reduced red cones; deuteranopia and deuteranomaly affect green cones; tritanopia and tritanomaly affect blue cones. Monochromacy is the complete absence of color perception.

Design implications: maintain 4.5:1 contrast for normal body text and 3:1 for large text; never rely on color alone to convey state; pair color with labels, icons, or patterns.