Value

online is a boolean true or false.

Examples

Basic usage

To check if you are online in a worker, query navigator.onLine, as in the following example:

if (navigator.onLine) {
  console.log("online");
} else {
  console.log("offline");
}

If the browser doesn't support navigator.onLine the above example will always come out as false/undefined.

Listening for changes in network status

To see changes in the network state, use addEventListener to listen for the events on online and offline, as in the following example:

addEventListener("offline", (e) => {
  console.log("offline");
});
addEventListener("online", (e) => {
  console.log("online");
});

Specifications

Browser compatibility