/Web APIs

Window: offline event

The offline event of the Window interface is fired when the browser has lost access to the network and the value of Navigator.onLine switches to false.


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


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

Event type

A generic Event.

Event handler aliases

In addition to the Window interface, the event handler property onoffline is also available on the following targets:



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

// onoffline version
window.onoffline = (event) => {
  console.log("The network connection has been lost.");


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
offline_event 3 12 9 9 15 4 ≤37 18 9 14 3 1.0

See also

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