This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The UIEvent.isChar read-only property returns a Boolean indicating whether the event produced a key character or not.


var isChar = UIEvent.isChar;


A Boolean which is true if the event produces a character; otherwise false. Some keystroke combinations may raise events but not produce any character (example: ctrl-alt-?). When this is the case, isChar returns false. It is used when event handlers need to do something like echo the input on the screen.


In this snippet, which is part of an event handler, the event is checked to see if it generates a character; if it does, the value of UIEvent.which is appended to a string which buffers the typed characters.

if (event.isChar) {
  characterBuffer += e.which;


This property is not part of any specification.

Browser compatibility

BCD tables only load in the browser

See also