HTML onunload Attribute - HTML Attribute

Definition and Usage

The onunload attribute fires once a page has unloaded (or the browser window has been closed).

onunload occurs when the user navigates away from the page (by clicking on a link, submitting a form, closing the browser window, etc.)

Note: If you reload a page, you will also trigger the onunload event (and the onload event).

Applies to

The onunload attribute is part of the Event Attributes, and can be used on the following element:

Elements	Event
<body>	onunload

Browser Support

How to Execute a JavaScript when a user unloads the document - HTML onunload Attribute

Click on F5 button to reload the page.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body onunload="myFunction()">

<h1>Welcome to my Home Page</h1>

<p>Close this window or press F5 to reload the page.</p>
<p><strong>Note:</strong> Due to different browser settings, this event may not always work as expected.</p>

<script>
function myFunction() {
  alert("Thank you for visiting W3Schools!");
}
</script>

</body>
</html>

Output should be:

html onunload attribute

Type:	Develop
Category:	Web Tutorial
Sub Category:	HTML Attribute
Uploaded by:	Admin

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