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This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

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

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Edge Firefox (Gecko) Internet Explorer Opera Safari
Basic support No support No support (Yes)[1] No support No support No support
Feature Android Edge Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support No support (Yes)[1] No support No support No support

[1] The isChar property has never been supported by any browser but Firefox, and even in Firefox it always returned false on any plaform other than macOS. For that reason, it's been removed in Firefox 55 to align with other browsers.

See also

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 Last updated by: Sheppy,