How to interpret the result
Missing events can indicate a hardware switch, matrix limitation, firmware mapping, browser shortcut, operating-system interception, or accessibility setting. Repeat outside the browser before concluding.
KB / 5 min
Online keyboard event and rollover test
Record keydown and keyup events, inspect codes, and see how many simultaneous keys the browser receives.
Local-firstNo accountExportable report
LIVE
LOCALLive test
0 simultaneous
Click here, then press keys
| Event | Key | Code | Repeat |
|---|
What this browser test can and cannot prove
The browser cannot distinguish all firmware-level ghosting, debounce quality, scan rate, switch chatter outside the event stream, or keys reserved by the operating system.
REPORT
Reports →Keep this result in a local inspection report.
RELATED
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Open testGamepad buttons and axes
Read connected gamepads, buttons, triggers, stick axes, timestamps, and mapping through the browser Gamepad API.
Open testKNOWLEDGE
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