Test every key on your keyboard in the browser
The Keyboard Tester is a fast way to check whether a keyboard is fully working without installing anything. Click the on-screen keyboard, then press each key in turn. Working keys flash green while held and keep a highlighted outline afterwards, so you can sweep across the whole board and instantly spot any key that never lit up.
It is the tool to reach for when you suspect a dead key, a stuck key, or a switch that double-types — common faults on both mechanical keyboards and laptop membranes, especially after a spill or heavy use.
What the readout shows
For every press the tester displays three values that developers and gamers often need:
- key — the character or name the key produces (for example
a,Enter,Shift). - event.code — the physical key position, independent of layout (for example
KeyA,ShiftLeft). - keyCode — the legacy numeric code, still used by some games and apps.
The keys registered counter tallies every distinct physical key you have pressed, which is handy for confirming a full pass across the keyboard.
Diagnosing common faults
A dead key never lights up no matter how firmly you press it — the switch or trace has failed. A stuck key stays green after you release it. A chattering or double-typing key fires more than one event for a single tap, which you will see as the last-key readout flickering. If a key works here but not in another app, the fault is more likely software (a remap, a stuck modifier, or a language layout) than the hardware itself.
Everything runs on your device. No keystroke is uploaded, logged or stored.