Blue-Yellow CVD

Free Tritanomaly
Test Online

Tritanomaly is partial blue-yellow color weakness—less severe than tritanopia. Screen with our free 18-plate test in under 2 minutes.

18-Plate Assessment

Free Online Color Blindness Test

Take our free Ishihara color blind test to check for red-green color blindness, deuteranopia, protanopia, and tritanopia. Get instant results with our scientifically-designed 18-plate color vision screening test. No registration required.

Optimal Setup
  • Disable dark mode and blue-light filters (Night Shift, f.lux)
  • Set screen brightness to at least 80%
  • Ensure you are in a neutral lighting environment
  • View screen from a normal reading distance
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What Is Tritanomaly?

Tritanomaly is a form of blue-yellow color vision deficiency where short-wavelength (S) cones exist but do not function normally. Colors along the blue-yellow axis are shifted rather than fully absent—as in complete tritanopia.

Tritanomaly vs Tritanopia

Tritanomaly vs tritanopia: tritanopia is dichromatic (no working S-cone channel); tritanomaly is anomalous trichromacy (weakened S-cones). Many people search for a tritanomaly test or mild tritanomaly screening—this 18-plate test flags blue-yellow patterns alongside red-green plates.

Design & Simulation

Preview UI under partial blue-yellow loss with our color blind simulator and adjust severity on the slider.