This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The Network Information API provides information about the system's connection in terms of general connection type (e.g., 'wifi', 'cellular', etc.). This can be used to select high definition content or low definition content based on the user's connection. The entire API consists of the addition of the NetworkInformation interface and a single property to the Navigator interface: Navigator.connection.

Note: This feature is available in Web Workers.


Detect connection changes

This example watches for changes to the user's connection.

var connection = navigator.connection || navigator.mozConnection || navigator.webkitConnection;
var type = connection.type;

function updateConnectionStatus() {
  console.log("Connection type changed from " + type + " to " + connection.type);

connection.addEventListener('change', updateConnectionStatus);

Preload large resources

The connection object is useful for deciding whether to preload resources that take large amounts of bandwidth or memory. This example would be called soon after page load to check for a connection type where preloading a video may not be desirable. If a cellular connection is found, then the preloadVideo flag is set to false. For simplicity and clarity, this example only tests for one connection type. A real-world use case would likely use a switch statement or some other method to check all of the possible values of NetworkInformation.type. Regardless of the type value you can get an estimate of connection speed through the NetworkInformation.effectiveType property.

let preloadVideo = true;
var connection = navigator.connection || navigator.mozConnection || navigator.webkitConnection;
if (connection) {
  if (connection.type === 'cellular') {
    preloadVideo = false;


Provides information about the connection a device is using to communicate with the network and provides a means for scripts to be notified if the connection type changes. The NetworkInformation interfaces cannot be instantiated. It is instead accessed through the Navigator interface.


Specification Status Comment
Network Information API
The definition of 'Network Information API' in that specification.
Draft Initial specification

Browser compatibility

We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 61 No support No support No support No support
Available in workers 61 No support No support No support No support
Feature Android Webview Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support 50 61 12.0 (12)[1] No support 37 No support
Available in workers 50 61 53.0 (53) No support 37 No support

[1] The Network API can be disabled using the dom.netinfo.enabled preference.

See also

Document Tags and Contributors

Last updated by: dhurlburtusa,