JS Keycode Tester
Press any key to inspect its event properties
Press any key…
How the keycode tester works
This tool listens for keydown events on the page and displays all properties from the KeyboardEvent object: event.key (the printable character or key name), event.code (the physical key position), keyCode / which (legacy numeric codes, still used in many codebases), and the four modifier-key booleans. Use event.key and event.code in modern code — keyCode is deprecated but still needed for older browser compatibility.
Private & free — this tool runs entirely in your browser.
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