Testing a keyboard before buying or after a spill
Walk the whole board row by row until every key shows green — that’s a full hardware pass. To test ghosting (cheap keyboards dropping keys in combos), hold several letters at once and check that all of them stay lit. After a liquid spill, retest daily for a while: corrosion failures appear gradually.
Frequently asked questions
How do I check if a key is broken?
Press it. If nothing lights up on the on-screen keyboard and no key info appears, the keyboard isn't sending that key — a hardware problem (dirt, worn switch or dead membrane). If it lights up here but doesn't work in some app, the problem is software (shortcuts, language layout or remapping).
How do I find a stuck key?
Without touching anything, look at the keyboard display: a key shown as held down (blue) that you're not pressing is stuck. Stuck modifier keys (Shift, Ctrl, Alt) explain weird typing behaviour like ALL CAPS or shortcuts firing on their own.
What's the difference between 'key' and 'code'?
code is the physical key position (KeyA, Digit1) independent of language layout; key is the character it produces with your current layout and modifiers (a, A, or Devanagari ब on a Nepali layout). If code fires but key looks wrong, your layout — not the hardware — is the issue.
Why don't some keys register?
The operating system or browser reserves a few combinations (like Ctrl+W or the Windows key alone), and laptop Fn keys are handled by firmware, invisible to the browser. Everything else should register here.