Keyboard test

How to use the keyboard test

1. Click anywhere inside the keyboard area first so it has focus, then start pressing keys.
2. Each key lights up green the moment it is detected, and stays green so you can see which keys you have already checked.
3. Work across every row, including the function keys (F1–F12), the arrows, and the numpad, until nothing is left grey.
4. Watch the “last key” readout — it shows the physical key and the character it produced, which is how you catch a wrong keyboard layout.

A key is not working / not responding

If a key stays grey when you press it, the browser never received it. Work through the likely causes from simplest to hardest:

• Dirt or debris — the most common cause for a single dead key. Power down, turn the keyboard over, and give it a firm shake; a can of compressed air under the keycap clears crumbs and dust.
• Connection — reseat the USB cable or receiver, or try a different port. For Bluetooth, re-pair the keyboard. A loose connection often kills a block of keys, not just one.
• Driver — on Windows, open Device Manager, expand Keyboards, right-click your keyboard and choose Uninstall device, then restart — Windows reinstalls a clean driver.
• Filter Keys — a Windows accessibility setting that ignores brief or repeated presses can make keys feel dead. Settings → Accessibility → Keyboard → turn Filter Keys off.

If the same key is dead in this test and in every app, it is hardware. If it works here but not in one app, the problem is that app's settings or a shortcut conflict.

A stuck or repeating key

A key that repeats on its own, or that this test shows as held down when you are not touching it, is usually physical. Crumbs, spilled liquid, or a worn key switch keep the contact closed. Pop the keycap off (gently — photograph the layout first), clean under it with isopropyl alcohol on a cotton swab, and let it dry fully before refitting. If a whole key feels mushy or sticky after a spill, the switch underneath may need replacing.

The keyboard types the wrong letters

If pressing one key produces a different character — Q types A, or the quote and @ are swapped — your keyboard hardware is fine; the operating system is using a different keyboard layout than the keyboard is physically built for (for example a US layout on a UK or German keyboard). This test shows both the physical key and the character it produced, so you can see the mismatch directly: press the key labelled Q here, and if the readout shows a different character, switch your layout. On Windows: Settings → Time & language → Language & region → your language → Options → add or set the matching keyboard. On macOS: System Settings → Keyboard → Input Sources.

Ghosting and N-key rollover

Ghosting is when a keyboard cannot register several keys pressed at once — press three or four together and one or more simply never appears. It mostly affects cheaper membrane keyboards and matters most for gaming, where you might hold a movement key, a modifier, and an action key together. To test it, hold down several keys at the same time and watch how many light up; the test tracks the most keys you registered simultaneously. A keyboard advertised as N-key rollover (NKRO) registers every key no matter how many you press. Built-in laptop keyboards often manage only 2–3 keys reliably, which is normal.

A whole row or half the keyboard is dead

When an entire row or one side stops responding — rather than a single key — the cause is rarely the individual switches. Keyboards are wired in a grid (a matrix), so one broken trace, a loose internal ribbon cable, or liquid damage takes out a line of keys at once. On a laptop this usually means the keyboard's ribbon connector has worked loose or corroded and needs reseating or replacement; on a desktop board, liquid that dried across the membrane is the usual culprit. An external USB keyboard is the quickest way to confirm the rest of the computer is fine.

The number pad (numpad) is not working

If the keys on the right-hand number pad do nothing, the cause is almost always a setting, not a fault:

• Num Lock — with Num Lock off, the numpad acts as arrows and Home/End instead of typing digits. Press Num Lock once and try again; the test shows whether the key registers.
• Mouse Keys — a Windows and macOS accessibility feature hijacks the numpad to move the cursor. Turn it off in Accessibility settings if the pad moves your pointer.
• Compact keyboards — many laptops and tenkeyless boards have no separate numpad at all, or fold it into the main keys behind an Fn layer.

Is this keyboard test safe? How it works

Yes. The test listens for your browser's standard keydown and keyup events — the same events every web page receives while it is open — purely to light up the on-screen keys. Nothing you type is recorded, stored, or sent anywhere, including to us, and the moment you leave the page it stops. It is not a keylogger and captures no text: it only notes which physical keys went down and came back up, never the words you form. A few keys are handled by your operating system or browser before any web page can see them — Win/⌘, and some function keys like F5, F11, and F12 — so they may not light up here even though they work fine.