Perception · Test
Spot the tile that is a slightly different colour. The difference keeps shrinking.
No account. No tracking. Your results stay with you.
One tile is different.
Find the tile with a slightly different colour. The difference shrinks every level. Three lives.
Needs colour and lightness vision; results depend on your screen's brightness and colour settings. This is a visual challenge, not a color-vision test.
This is a visual challenge, not a color-vision test. One tile is a slightly different colour from the rest. Select it. The colours are random each level; the difference is measured in OKLab, a colour space designed so equal distances look roughly equally different.
The difference starts at 25 units (ΔE_ok × 100) and shrinks by 14% per level to a floor of 0.6. The grid grows from 2×2 to 6×6. A wrong tile costs a life and repeats the level with new colours. Three lives; the run ends at level 30.
score = highest level completed difference = ΔE_ok × 100 between the shown colours
The smallest difference you found is shown too, measured from the exact 8-bit colours displayed (not the intended ones).
The test runs entirely in this browser tab. Results are saved only in this browser's local storage so you can compare with yourself — never uploaded, never tracked. You can clear them any time.