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Window: blur event

The blur event fires when the window has lost focus, for example when the user moves focus from the page to the address bar. Focus may previously have been on the document's viewport or on an element within it.

The opposite of blur is focus.

This event is not cancelable and does not bubble.

Syntax

Use the event name in addEventListener():

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

Alternatively, assign to the event handler property of the interface:

onblur = (event) => { }

Event type

A FocusEvent. Inherits from UIEvent and Event.

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: #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

See also