Window: offline event

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

Theoffline event of theWindow interface is fired when the browser has lost access to the network and the value ofNavigator.onLine switches tofalse.

Syntax

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

addEventListener("offline", (event) => { })onoffline = (event) => { }

Event type

A genericEvent.

Event handler aliases

In addition to theWindow interface, the event handler propertyonoffline is also available on the following targets:

Examples

// addEventListener versionwindow.addEventListener("offline", (event) => {  console.log("The network connection has been lost.");});// onoffline versionwindow.onoffline = (event) => {  console.log("The network connection has been lost.");};