Keyboard Test — Check Every Key Online
Press any key to see event.key, event.code and keyCode, with a press history and per-key counters. Great for finding broken keys. Runs locally — no keystrokes are recorded or sent.
🔒 Runs entirely in your browser. Your input and output are never sent to a server or stored — fully private.
🔒 Keystrokes are processed only in your browser — nothing is recorded or sent anywhere.
About this tool
Suspect a broken key? Press anything and this keyboard tester reacts instantly, showing the exact event.key and event.code values your browser receives, logging a history of presses and counting how many times each key has registered. Sweep across the whole board to confirm every key still responds after a spill or a cleaning, check a second-hand purchase before paying, or use the codes to debug shortcuts and key remapping. It all runs locally: keystrokes are processed on your device only and are never logged to a server or transmitted anywhere.
Frequently asked questions
What is the difference between event.key and event.code?
event.key is the character or action the press produces, taking your keyboard layout into account — the key labelled Q gives 'q' on a QWERTY layout but 'a' on AZERTY. event.code identifies the physical position, so that same key always reports 'KeyQ' regardless of layout or language. Use key when you care about what gets typed, and code when you care about which physical key was pressed, as games usually do.
Why do some keys stop registering when I hold several at once?
That is keyboard ghosting, a hardware limit rather than a defect. Most membrane keyboards share circuit lines between keys and can only report certain combinations of three or more keys; extra presses are simply dropped to avoid phantom input. Gaming keyboards advertise N-key rollover (NKRO) to remove this limit. If a combination fails here, it will fail in games too — try spreading the keys further apart or switching to a keyboard with NKRO.
Are my keystrokes recorded, and why do a few keys not show up?
Everything is processed locally in your browser — no keystroke is stored on a server or sent anywhere, so you can type freely. A few keys may still stay invisible: Fn is handled inside the keyboard hardware and never reaches the browser, and the operating system or browser can intercept keys like Print Screen or the media keys before the page sees them. That is normal behaviour, not a sign that those keys are broken.