Online status

The navigator.onLine property is a boolean for whether the browser is connected to some network (though not necessarily the internet). The online and offline events fire when the connection state changes.

Baseline Status: Achieved Widely Available on Jan 29, 2018 (Cross-browser Newly Available since Jul 29, 2015).

Desktop Browser Engine Support

Google Chrome

2

Supported

Mozilla Firefox

1.5

Supported

Apple Safari

4

Supported

Microsoft Edge

12

Supported

Mobile Browser Engine Support

Chrome Android

18

Firefox Android

4

Safari iOS

3.2

Specifications and References

Specification ↗ Specification ↗ Can I Use (online-status) ↗ Feature XML ↗

MDN Browser Compat Data Keys:

api.Navigator.onLine ↗ api.Window.offline_event ↗ api.Window.online_event ↗ api.WorkerGlobalScope.offline_event ↗ api.WorkerGlobalScope.online_event ↗ api.WorkerNavigator.onLine ↗