Guess the Length
How much of the reference line does the coloured bar fill?
How to use
Guess the coloured width as a percentage of the full reference line over five rounds.
Use the on-screen feedback to finish the challenge.
Start a fresh round or save a result when available.
FAQ
How does it work?
Guess the coloured width as a percentage of the full reference line over five rounds.
What should I know?
The ratio stays the same across screen sizes. The game measures a proportion, not physical centimetres.
Do I need an account?
No. Game state stays in this browser. There is no server leaderboard or multiplayer synchronization.