It is also a stuck-key test
Beyond the game, this is a quick way to check a spacebar that has started missing presses or registering two from one. A count that runs ahead of your presses means switch bounce; one that lags means debris under a large key, which is where crumbs collect.
For the rest of the board, the keyboard tester shows every key at once.
Key repeat is not counted
Holding the spacebar makes the operating system emit repeats, which would inflate any honest count. Repeats are ignored here, so the number reflects actual presses — which is also why holding it down achieves nothing.
Frequently asked questions
Can I hold the spacebar down?
It will not count. Operating system key repeat is ignored, so only real presses register.
The count is higher than my presses. Why?
Switch bounce — the contacts making and breaking rapidly on one press. It is a sign the switch is wearing out.
What is a good score?
Around six to eight presses a second is typical. Much beyond that usually means a technique rather than speed.
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