Keycode tester
Press a key or shortcut to see its character, position code and modifiers. Follow the down and up sequence, or open the event log for details.
Press and release any key to see its event sequence.
What the test received
Press and release a key to begin.
A key, shortcut or remap sends an unexpected value
Key is the reported character or action; code identifies a physical position. They can differ normally with another input layout. Repeat flags describe held-key repetition, while composing events belong to an input method.
Compare one press and release
Reset and press the affected key once. Compare its code, key and left/right location. Use the layout checker for wrong characters and the Key Press Counter for additional taps.
Check the expected system action
If a shortcut opens another window or Print Screen starts a screenshot tool, it may be intercepted before this page receives it. Test an ordinary letter to confirm focus.
Review the active mapping
Check the input layout and your keyboard’s documented Fn layer or Windows/Mac mode. Save remap or macro profiles before comparing a normal profile.
Compare in the target app
Repeat the same action in another app or browser. Compare the character, position code and modifiers.
Retest
Clear history and repeat the same key or shortcut. Copy the latest event only if you want to share it; review the export before sending it to anyone.
If it persists
For a failure that also occurs outside the browser, ask the keyboard maker or remapping-software provider about that exact model and mapping.