Window: blur event

The blur event fires when an element has lost focus.

The opposite of blur is {{domxref("Window/focus_event", "focus")}}.

This event is not cancelable and does not bubble.

Syntax

Use the event name in methods like {{domxref("EventTarget.addEventListener", "addEventListener()")}}, or set an event handler property.

js-nolint

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

onblur = (event) => { }

Event type

A {{domxref("FocusEvent")}}. Inherits from {{domxref("UIEvent")}} and {{domxref("Event")}}.

Event properties

This interface also inherits properties from its parent {{domxref("UIEvent")}}, and indirectly from {{domxref("Event")}}.

{{domxref("FocusEvent.relatedTarget")}}
- : An {{domxref("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 {{domxref("EventTarget.addEventListener()", "addEventListener()")}} to monitor {{domxref("Window/focus_event", "focus")}} and blur events.

HTML

html

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

CSS

css

.paused {
  background: #dddddd;
  color: #555555;
}

JavaScript

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

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.";
}

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

Result

Specifications

Browser compatibility

The value of {{DOMxRef("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.