Color Discrimination Test
A staircase test of how fine a color difference your eyes can resolve. Every round shows a grid of identical tiles with exactly one odd tile whose hue and lightness are nudged by a small delta; click the odd one out. Each correct pick shrinks the delta and grows the grid, so the game homes in on your personal discrimination threshold; a miss backs the difficulty off so you are always hovering near your limit — the same adaptive logic real psychophysics uses. Play the 60-second timed mode and chase a level score, or the untimed practice mode to explore where your threshold sits. Color vision varies a lot between people — and between screens — so your best level is stored on this device, where the comparison is fair.
Runs 100% in your browser — your puzzles never leave your device.
Read the full guide to this tool
Notes
- The adaptive staircase (harder on success, easier on a miss) keeps you near threshold, which measures discrimination far more efficiently than fixed difficulty levels would.
- Late levels are genuinely at the edge of human vision: a just-noticeable color difference under good conditions corresponds to a tiny fraction of the hue-lightness nudges used in the early rounds.
- Screens matter: panel type, color profile, brightness and viewing angle all change how visible a given delta is — compare scores on the same display, and expect a boost from a good IPS or OLED panel.
- Runs 100% in your browser — your words and puzzles never leave your device.
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