⭐ 0
🔍
Text Image PDF & Docs Audio Music Electronics Time Utilities Validators Esoteric Games

Keyboard Tester

Press any key and watch it light up on an on-screen keyboard: check every switch, count simultaneous keys and spot dead or chattering keys.

EscF1F2F3F4F5F6F7F8F9F10F11F12
`1234567890-=⌫
TabQWERTYUIOP[]\
CapsASDFGHJKL;'Enter
ShiftZXCVBNM,./Shift
CtrlMetaAltAltMetaMenuCtrl
◀▲▼▶

0
0
0
0

Processing... 0%

Result

Spilled coffee on your keyboard, bought a second-hand mechanical board, or suspect one switch double-types or stopped registering? A keyboard tester answers those questions in seconds: press every key and watch the on-screen layout light up.

Keys that are currently held glow in one color; every key that has registered at least once stays marked in another. Walk across all rows, and any key that never changes color is a dead switch. The history line shows the exact key codes the browser received, which also helps identify keys that fire twice (chatter).

The simultaneous-keys counter tracks how many keys are registered at the same moment and keeps the maximum — a quick way to observe rollover and ghosting behavior on your board. Be aware that the browser and the operating system may cap how many simultaneous keys they report, so a low number is not always the keyboard's fault.

Everything happens locally through standard KeyboardEvent APIs: no keystroke leaves your device, no permissions are requested, and the tester works the same on Windows, macOS and Linux.

🛡️
Executed in Browser

Your files and inputs never leave this device. Processing runs completely offline. 100% Secure.

Accepted Formats & Rules

  • On-screen ANSI keyboard that reacts to real keydown and keyup events via KeyboardEvent.code.
  • Press history line, total press counter and a dedicated spacebar counter.
  • Tab, Space, F-keys and quote keys are intercepted during the test so the browser does not hijack them.

Key Benefits

✓ Nothing to install: the tester runs entirely in your browser and starts the moment the page loads.
✓ Two-color feedback: keys that are held down light up one way, keys that have ever registered stay marked — so you always know which switches were already tested.
✓ Rollover insight: a live counter shows how many keys the browser reports as held at once and remembers the maximum reached.

Use Cases

  • • Check every key of a second-hand or repaired keyboard: walk across the rows and any key that never lights up is dead.
  • • Hold WASD plus Space and Shift to see how many keys your board registers at once before buying it for gaming.
  • • Verify a key you suspect of double-typing (chatter) by comparing the press history with the number of physical presses.