Barcode scanner tool
Keyboard Event Tester
See exactly what your browser receives for every keystroke: key, code, location, timestamp, and modifier state. Useful for diagnosing scanner output at the lowest level a web page can observe.
Before you start
Click Start, then scan a barcode or type on your keyboard anywhere on this page. Every keydown, keyup, and keypress event will be logged below with full detail, in the order it was received.
Event log
Status: Stopped · 0 events logged
| Type | Key | Code | Location | Timestamp | Ctrl | Alt | Shift | Meta |
|---|---|---|---|---|---|---|---|---|
| No events logged yet. | ||||||||
Note: keyboard events shown here are browser-level events. They do not represent raw USB HID packets or driver data.
Reading the location column
The KeyboardEvent.location property tells you which physical key produced the event when a key exists in more than one place on the keyboard.
- Standard — the main key, not a duplicated key
- Left / Right — distinguishes duplicated modifier keys such as Shift, Ctrl, or Alt
- Numpad — the key was produced by the numeric keypad, common for scanners that emit digits via numpad codes
Why this matters for scanners
Some scanners emit digits using numpad key codes rather than the top-row number keys, which can confuse keyboard shortcut handlers or input masks. Others send characters with unexpected modifier flags if the scanner's configured keyboard layout does not match the OS layout. This log surfaces both issues directly.
Related
To see a decoded, assembled scan result instead of raw events, use the Barcode Input Tester. For background on why scanners emit these patterns, read HID Keyboard Wedge Explained.