Keyboard test
Press physical keys and watch the matching key light up. Verified keys stay marked until reset.
The diagram is a full-size ANSI reference. Laptop, compact, ISO, and TKL boards may omit or reposition keys. The test uses event.code, so it checks the physical key position even when your operating-system layout prints a different character. On mobile, use a paired hardware keyboard. On-screen keyboards rarely expose every hardware code.
Browser and operating-system shortcuts can intercept keys such as the Windows key, Command key, power key, media keys, Print Screen, and some function-key combinations before the page sees them. A missing mark for one of those keys does not automatically mean the switch is faulty.
Last updated: July 25, 2026
Keyboard test: A keyboard test should tell you more than whether letters appear in a text box. This one maps physical key positions with event.code, marks every verified key, and keeps a running count so you can work methodically across the board.
How this keyboard test works
Click the tester, then press and release one key at a time. A key highlights while held and stays lightly marked after release. Work across each row, including both Shift, Control, Alt, arrow, navigation, and number-pad keys that exist on your board. The detected code is more useful for hardware diagnosis than the printed character because software layouts can remap what a position types.
How to read the results
One clean press should produce one press count and one verified position. If a key never lights, test it in another browser and in a plain text editor. If it lights as the wrong physical position, check keyboard-remapping software and operating-system layout settings. Repeated presses from one tap can point to switch chatter, debris, firmware settings, or a failing membrane.
Common causes of failed tests
Common causes include crumbs under a keycap, liquid damage, a worn mechanical switch, a damaged laptop ribbon cable, a low wireless battery, Bluetooth interference, accessibility settings, gaming software profiles, and a USB hub that is dropping input. Reserved shortcuts are a special case: the browser may never receive them even when the hardware is fine.
Troubleshooting before you replace hardware
Reconnect the board directly to the computer, remove any passive adapter, and retest. For a wireless board, charge it and try its receiver in a different port away from USB 3 radio noise. Test the same key in the firmware setup screen or another computer when possible. Do not pull laptop keycaps unless the service guide says they are removable.
For setup and buying context, see the Ergonomic desk setup checklist and desk space planner.
Frequently asked questions
Why does the keyboard test use event.code?
It identifies the physical key position instead of the character produced by the current language layout.
Why can some keys not be tested?
The operating system or browser can reserve system, media, power, and shortcut keys before the page receives them.
Does it work with laptop keyboards?
Yes. Use the keys your laptop has and ignore missing sections such as the number pad.