HTML onblur Attribute - HTML Attribute

Definition and Usage

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.

Applies to

The onblur attribute is part of the Event Attributes, and can be used on any HTML elements.

Elements	Event
All HTML elements	onblur

Browser Support

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

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>

Output should be:

html onblur attribute

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

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