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Tritanopia Design

How to design interfaces that work for tritanopes — the rare blue-yellow color blindness.

Published November 15, 2026 · 5 min read

What Tritanopes See

Tritanopia is a rare form of color blindness where blue cones are missing. Blues appear shifted toward green, greens look bluish-gray, and yellows may look pinkish or gray. It affects roughly 1 in 10,000 people — much rarer than red-green CVD.

Because it is rare, tritanopia is rarely considered during design. But it is the most common type of blue-yellow color blindness and worth testing for.

Key Distinguishing Features

Blue ↔ Green confusion — both appear as blue-green blends
Yellow ↔ Pink confusion — both can appear washed-out
Red remains distinct — reds are largely unaffected
Blue darkens — similar effect to red under protanopia

Colors That Fail for Tritanopes

Blue ↔ Green (both look bluish)
Yellow ↔ Pink (both look pale)
Light blue ↔ Cyan ↔ Teal (all merge)

The Blue-Link Problem

Tritanopes often have trouble distinguishing blue links from surrounding text — not because blue fails, but because specific blue hues shift toward gray. A blue link on a black-and-white page is usually visible, but a blue link on a colorful page is more likely to be missed.

Solution: underline links in body content. This non-color signal works for every CVD type including tritanopia.

Recommended Palette for Tritanopes

Primary: Red #DC2626 (highly distinguishable)
Secondary: Yellow #FBBF24 (distinct from red)
Success: Deep green #15803D (dark enough to distinguish)
Warning: Orange #EA580C
Error: Deep magenta #BE123C

Red, orange and magenta remain well distinguished under tritanopia. Avoid blue-green hues for critical information.

Charts and Dashboards

Blue and green category colors are the most common failure for tritanopes. Use lightness variation to distinguish blue from green — a dark blue and a light green will always be distinguishable by lightness, even if hue is confused.

Add line styles, patterns or direct labels to reinforce series distinction.

Testing

Use our Color Blindness Simulator to preview through the tritanopia filter. Because tritanopia is rare, this is often skipped — but the simulators implement it exactly as the standard algorithm.