Web/API/KeyboardEvent/which

DeprecatedThis 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 which read-only property of the KeyboardEvent interface returns the numeric keyCode of the key pressed, or the character code (charCode) for an alphanumeric key pressed.

Syntax

var keyResult = event.which;

Return value

keyResult contains the numeric code for a particular key pressed, depending on whether an alphanumeric or non-alphanumeric key was pressed. Please see KeyboardEvent.charCode and KeyboardEvent.keyCode for more details.

Example

<html>
<head>
<title>charCode/keyCode/which example</title>

<script type="text/javascript">

function showKeyPress(evt) {
alert("onkeypress handler: \n"
      + "keyCode property: " + evt.keyCode + "\n"
      + "which property: " + evt.which + "\n"
      + "charCode property: " + evt.charCode + "\n"
      + "Character Key Pressed: "
      + String.fromCharCode(evt.charCode) + "\n"
     );
}


function keyDown(evt) {
alert("onkeydown handler: \n"
      + "keyCode property: " + evt.keyCode + "\n"
      + "which property: " + evt.which + "\n"
     );
}

</script>
</head>

<body
 onkeypress="showKeyPress(event);"
 onkeydown="keyDown(event);"
>

<p>Please press any key.</p>

</body>
</html>

Specifications

Specification	Status	Comment
Document Object Model (DOM) Level 3 Events SpecificationThe definition of 'KeyboardEvent.which' in that specification.	Obsolete	Initial definition; specified as deprecated

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`which` Deprecated'Non-standard'	Chrome Full support 4	Edge Full support 12	Firefox Full support 2 Notes' Full support 2 Notes' Notes' Firefox also implements this property on the `UIEvent` interface.	IE Full support 9	Opera Full support 12.1	Safari Full support 5.1	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support Yes Notes' Full support Yes Notes' Notes' Firefox also implements this property on the `UIEvent` interface.	Opera Android Full support 12.1	Safari iOS Full support 5.1	Samsung Internet Android Full support Yes

Legend

Full support: Full support
Non-standard. Expect poor cross-browser support.': Non-standard. Expect poor cross-browser support.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
See implementation notes.': See implementation notes.