Window: focus event

The focus event fires when an element has received focus.

The opposite of focus is blur.

This event is not cancelable and does not bubble.

Syntax

Use the event name in methods like addEventListener(), or set an event handler property.

addEventListener('focus', event => { });

onfocus = event => { };

Event type

An FocusEvent. Inherits from Event.

Event properties

This interface also inherits properties from its parent UIEvent, and indirectly from Event.

FocusEvent.relatedTarget: An EventTarget representing a secondary target for this event. In some cases (such as when tabbing in or out a page), this property may be set to null for security reasons.

Examples

Live example

This example changes the appearance of a document when it loses focus. It uses addEventListener() to monitor focus and blur events.

HTML

<p id="log">Click on this document to give it focus.</p>

CSS

.paused {
  background: #ddd;
  color: #555;
}

JavaScript

function pause() {
  document.body.classList.add('paused');
  log.textContent = 'FOCUS LOST!';
}

function play() {
  document.body.classList.remove('paused');
  log.textContent = 'This document has focus. Click outside the document to lose focus.';
}

const log = document.getElementById('log');

window.addEventListener('blur', pause);
window.addEventListener('focus', play);

Result

Specifications

Specification
UI Events # event-type-focus

Browser compatibility

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