How to use
- Press Start. The 60-second timer begins.
- Tap the tile whose color is slightly different from the rest.
- Each correct tap moves you up a level. A wrong tap costs 3 seconds.
- When time runs out, see your level and share it.
What does the score mean?
Early levels differ by a large step in lightness; later levels differ by only 2 points on a 0–100 scale, which is hard to see on many screens. Screen brightness, color settings and room lighting all affect the result, so this is a game, not a medical color vision test.
Frequently asked questions
Is this a color blindness test?
No. It measures how well you notice small lightness differences on your screen. For color vision deficiency, see an eye care professional.
Why is it harder on my phone?
Small tiles and automatic brightness or night mode make subtle differences harder to see. Try turning off night mode.
Is my best score saved?
Yes, in this browser.