This small online tool allows to know the key, keyCode and code associated with any key (Except Fn ...).
When you press any key, it shows you the event.key, event.keyCode and event.code read-only properties.
Warning, keyCode is deprecated! You should avoid using this if possible. Instead, you should use event.code.
The event.code property represents a physical key on the keyboard.
These codes are sometimes useful when you want to capture the press on certain keys (for example, pressing Ctrl + C or Ctrl + V).