Web/API/KeyboardEvent/altKey

The KeyboardEvent.altKey read-only property is a Boolean that indicates if the alt key (Option or ⌥ on OS X) was pressed (true) or not (false) when the event occured.

Syntax

var altKeyPressed = instanceOfKeyboardEvent.altKey

Return value

Boolean

Examples

<html>
<head>
<title>altKey example</title>

<script type="text/javascript">

function showChar(e){
  alert(
    "Key KeyDown: " + String.fromCharCode(e.charCode) + "\n"
    + "charCode: " + e.charCode + "\n"
    + "ALT key KeyDown: " + e.altKey + "\n"
  );
}

</script>
</head>

<body onkeydown="showChar(event);">
<p>
Press any character key,
with or without holding down the ALT key.<br />
You can also use the SHIFT key together with the ALT key.
</p>
</body>
</html>

Specifications

Specification	Status	Comment
Document Object Model (DOM) Level 3 Events SpecificationThe definition of 'KeyboardEvent.altkey' in that specification.	Obsolete	Initial definition.

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
`altKey`	Chrome Full support Yes	Edge Full support 12	Firefox Full support Yes	IE Full support Yes	Opera Full support Yes	Safari Full support Yes	WebView Android Full support Yes	Chrome Android Full support Yes	Firefox Android Full support Yes	Opera Android Full support Yes	Safari iOS Full support Yes	Samsung Internet Android Full support Yes

Legend

Full support: Full support

Web/API/KeyboardEvent/altKey

Contents

Syntax

Return value

Examples

Specifications

Browser compatibility

Legend

See also