HTML onblur Event Attribute - HTML Form Events Attribute

The HTML onblur event attribute specifies a script to be executed when an element loses focus. This event is triggered when a user moves away from an element that currently has focus, such as clicking outside of a text input field or navigating to another element using the Tab key .

Example of HTML onblur Event Attribute

Here validates an input field when the user leaves it.

index.html

Example: HTML

 <input type="text" name="fname" id="fname" onblur="myFunction()">

Output should be:

Definition and Usage of HTML onblur Event Attribute

The onblur attribute fires the moment that the element loses focus.

Onblur is most often used with form validation code (e.g. when the user leaves a form field).

Tip: The onblur attribute is the opposite of the onfocus attribute.

Browser Support of HTML onblur Event Attribute

Syntax of HTML onblur Event Attribute

<element onblur="script">

Attribute Values of HTML onblur Event Attribute

Value	Description
script	The script to be run on onblur

Technical Details of HTML onblur Event Attribute

Supported HTML tags:	All HTML elements, EXCEPT: <base>, <bdo>, <br>, <head>, <html>, <iframe>, <meta>, <param>, <script>, <style>, and <title>

How to validate an input field when the user leaves it

When you leave the input field, a function is triggered which transforms the input text to upper case.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body>

Enter your name: <input type="text" name="fname" id="fname" onblur="myFunction()">

<p>When you leave the input field, a function is triggered which transforms the input text to upper case.</p>

<script>
function myFunction() {
  let x = document.getElementById("fname");
  x.value = x.value.toUpperCase();
}
</script>

</body>
</html>

Output should be:

How to use "onblur" together with the "onfocus" attribute

When you enter the input field, a function is triggered which sets the background color to yellow. When you leave the input field, a function is triggered which sets the background color to red.

index.html

Example: HTML

 <input type="text" onfocus="focusFunction()" onblur="blurFunction()">

Output should be:

html event attributes

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

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