Verify every key on your keyboard with our free Keyboard Tester. Press physical keys to illuminate an interactive virtual QWERTY board, read KeyboardEvent.code values per press, test multi-key rollover behavior, and identify stuck or ghosting keys — all 100% offline with zero keystroke logging.
KeyboardEvent.code for hardware-layout-independent key identificationClick anywhere on the page to focus, then press any key on your physical keyboard.
Matched virtual key tiles illuminate with your accent color while the key is held down.
Read the active key name and code value, and press multiple keys to test rollover.
Uses KeyboardEvent.code (hardware scan codes) rather than .key, enabling layout-independent detection regardless of keyboard locale mapping.
Hold multiple keys simultaneously — tiles that illuminate confirm rollover support. Missing tiles reveal ghosting limitations in your keyboard's controller.
All keydown/keyup events are handled exclusively in local browser memory. No key input data is ever sent to BunchTool servers.
The browser's KeyboardEvent.code property identifies the physical key location on the keyboard (e.g. KeyA, ShiftLeft) independent of locale mapping, while KeyboardEvent.key returns the character produced by the key (affected by modifier states).
Keyboard rollover is categorized as: 2-key rollover (2KRO — common on membrane keyboards), 6-key rollover (6KRO — standard on most quality keyboards), and N-key rollover (NKRO — gaming/mechanical keyboards). Ghosting produces false keypress reports when a matrix circuit cannot isolate simultaneous switch states.
Browser keyboard capture has OS-level limitations: system shortcuts (e.g. Win/Cmd, Fn) bypass the browser event stack. The preventDefault() call on Space and Tab prevents the page from scrolling or defocusing during testing.