Press a key. If it lights up, the keyboard reported it correctly.
Keys tested: 0 of 0
Nothing pressed yet.
Everything above runs inside this page. Your keystrokes are not recorded, not stored and not sent anywhere — this page makes no network request at all while you use it.
The key is not reaching the computer. Before assuming the switch died, press it hard and off-centre: a cap sitting on debris makes contact only sometimes.
Next step: Pop the keycap off and blow the socket out. On a mechanical board with hot-swap sockets a single switch is a two-minute swap; on a membrane keyboard the sheet is one part, so a dead key usually ends it.
The keyboard sends the press but never the release. This is what produces the classic symptom of one character repeating without end.
Next step: Unplug the keyboard: if the repeat stops immediately, it is the hardware and not the operating system. Clean under the cap first — sticky residue causes this far more often than a failed switch.
Switch chatter. The contact bounces and the keyboard reports two presses for one movement of your finger.
Next step: On a mechanical keyboard, contact cleaner into the switch fixes a fair share of cases. If it comes back, the switch is worn.
Keyboard fine? The next thing people check is usually the microphone, or run everything at once from the device summary.
| Approach | Best for | Trade-off |
|---|---|---|
| Type into a text field | A quick sanity check when you only doubt one or two letters | Says nothing about modifiers, function keys or a key that repeats on its own — a text field swallows all three |
| The keyboard panel in the operating system | Windows on-screen keyboard or macOS Keyboard Viewer, when you suspect a driver rather than hardware | Shows the key the system decided on, so a remapped or hijacked key still looks correct |
| The vendor utility for a gaming keyboard | Per-key RGB boards, where the utility can test the switch itself | Install required, one brand only, and it will not run on a work machine you do not administer |
| This page | Any keyboard on any computer, including one you are not allowed to install software on | Sees only what the browser is given: the Fn key and some laptop media keys never reach it |
Where this stops being the right tool — and what to use instead.
Fn is handled by the keyboard controller before the operating system. No browser on any platform receives it, so a page cannot report on it.
Next step: Test what Fn does instead: hold it and press a function key, and see whether the paired action happens.
If nothing at all registers, the fault is upstream of the browser — cable, USB port, Bluetooth pairing or a driver.
Next step: Try a different port, another computer, and a wired connection before blaming the keys.
This is a hardware check, not a typing trainer: it counts which keys responded, not how fast you produce words.
Next step: Use a typing site for speed. The two answer different questions and mixing them helps neither.
The on-screen keyboard sends text, not physical key positions, so the map stays grey however hard you type.
Next step: Attach a physical keyboard, or open this page on the computer whose keyboard you doubt.
