Keyboard Tester

Test every key on your keyboard against a visual layout. Spot dead keys, switch chatter and rollover limits, and inspect the raw key codes your browser receives.
of keys registered
Presses: Max held at once: Possible chatter:
Every key on this layout responded. Your keyboard passed the test.
Not pressed yet Held down Registered OK Possible chatter

Last key event

Press any key to begin.

Rollover & issues

Currently held
Nothing held.
Hold several keys at once to check rollover / NKRO. Best so far: .
Possible chatter

No double-firing detected.

These keys fired again within 45 ms of releasing — a classic sign of a worn or dirty switch.

Untested keys

All keys covered.

Event log

Key events will appear here.

A few keys are swallowed by the operating system or the browser before the page ever sees them — typically F11, F12, Alt+Tab, Cmd+Tab, PrintScreen (on some systems) and the Windows / ⌘ keys. If one of those stays grey, test it outside the browser before assuming the switch is dead. You can also click a key with the mouse to mark it manually.

Features

  • Live visual keyboard: every key lights up while it is held and turns green once it has registered.
  • Three layouts — full size 104-key, tenkeyless 87-key and compact 65%.
  • Chatter detection flags switches that fire twice within 45 ms of being released.
  • Rollover / NKRO check: see how many keys your board reports at the same time.
  • Raw event inspector showing event.code, event.key, keyCode and key location, plus a scrolling event log.
  • Running list of keys you have not pressed yet, so nothing gets missed.
  • Everything runs in your browser — no keystroke ever leaves the page.

How to Use

  1. Pick the layout that matches your keyboard (full size, TKL or 65%).
  2. Click anywhere on the page, then press every key one by one — each one turns green when it registers.
  3. Watch the Untested keys list shrink; anything left over is worth a second look.
  4. Hold four or more keys at once to test rollover, and check the Max held at once counter.
  5. Tap a suspect key rapidly — if it appears under Possible chatter, the switch is likely worn or dirty.
  6. Press Reset test to clear the results and start over.