Test every key, spot chatter, and check multi-key combinations in your browser.
Click Focus tester, then press keys on your keyboard. The matching key lights up while held, stays marked after release, and records a press count. Use the event log to confirm the exact key code your browser received.
A key that appears in the current-combination display when you are not pressing it may be physically stuck or sending a continuous signal. This is common on keyboards that have had liquid spilled on them.
If a key does not highlight or appear in the event log when pressed, either the switch has failed or the key is not being recognised by your operating system. Try pressing it in a text editor to confirm.
Mechanical keyboard switches can develop "chatter" — where one physical press registers as two keystrokes. Test by pressing a suspect key slowly and watching the press badge and event log. If the count jumps twice from one physical press, that switch may be chattering.
Hold several keys at once and watch the current-combination display. If one of the keys you are physically holding does not appear, that combination may exceed your keyboard's rollover support.
If you've switched between keyboard layouts (e.g. QWERTY to Dvorak, or UK to US), this tester helps you verify which physical key maps to which label in your current OS layout.
Yes. All key detection happens locally in your browser using JavaScript event listeners. No keystrokes are recorded, transmitted, or stored anywhere.
Once your keyboard is confirmed working, take a 1-minute typing test to see your current WPM, or try a targeted practice session to work on specific keys.
Click Focus tester, then watch the current-combination display before pressing anything. A key shown as held while your hands are off the keyboard is stuck — usually from debris or spilled liquid under the keycap. Then press every key in turn and confirm each one highlights and releases cleanly.
Ghosting is when a keyboard cannot register certain combinations of simultaneous key presses, so one of the keys is silently dropped. It happens because budget keyboards share circuit lines between keys. Hold three or four keys here and check whether every one appears in the display; a missing key reveals the limit.
That is switch chatter: a worn or dirty mechanical switch makes and breaks contact several times during one press, so the computer registers two keystrokes. Press the suspect key slowly and watch its press counter in the tester — if the count jumps by two, the switch needs cleaning or replacement.