Designing Accessible Color Palettes: Contrast and Color Blindness Simulation

Accessible color design ensures that every user—regardless of vision deficiencies—can navigate and comprehend your user interface. Roughly 8% of men and 0.5% of women have some form of color vision deficiency (CVD).

Audit and simulate your designs with our free browser-based tools:

• Test whole palettes with the Palette Accessibility Checker
• Preview how colors appear to color-blind users with the Color Blindness Simulator

Common Types of Color Vision Deficiencies

1. Deuteranopia & Deuteranomaly (Green-weak/blind): The most common type (approx. 6% of males). Red and green hues blend together, and greens appear muted or yellowish.
2. Protanopia & Protanomaly (Red-weak/blind): L-cone photoreceptors are missing or defective. Red appears dark and can be confused with black or brown.
3. Tritanopia & Tritanomaly (Blue-weak/blind): S-cone deficiency. Blues appear greenish, and yellows look pink or light gray.
4. Achromatopsia (Total color blindness): Rare complete absence of color perception; users perceive luminance differences only.

WCAG Contrast Requirements

The Web Content Accessibility Guidelines (WCAG) 2.2 specify strict contrast ratios between foreground text and background colors:

Best Practices for Accessible UI Design

• Never rely on color alone: Pair status colors with icons or text labels (e.g. a checkmark icon with a green success badge, or an exclamation icon with a red error badge).
• Use high luminance contrast: When colors are converted to grayscale, elements should remain clearly distinct.
• Audit whole palettes simultaneously: Rather than testing individual buttons, run your entire token library through the Palette Accessibility Checker to verify all interactive pairings.