Window: blur event

The blur event fires when an element has lost focus.

The opposite of blur is focus.

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("blur", (event) => {});

onblur = (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

html

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

CSS

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-blur
HTML Standard # handler-onblur

The value of Document.activeElement varies across browsers while this event is being handled (Firefox bug 452307): IE10 sets it to the element that the focus will move to, while Firefox and Chrome often set it to the body of the document.