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NetworkInformation: downlinkMax property

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

The NetworkInformation.downlinkMax read-only property returns the maximum downlink speed, in megabits per second (Mbps), for the underlying connection technology.

Note: This feature is available in Web Workers

Value

An unrestricted double representing the maximum downlink speed, in megabits per second (Mb/s), for the underlying connection technology.

Examples

The following example monitors the connection using the change event and logs changes as they occur.

js

function logConnectionType() {
  let connectionType = "not supported";
  let downlinkMax = "not supported";

  if ("connection" in navigator) {
    connectionType = navigator.connection.effectiveType;

    if ("downlinkMax" in navigator.connection) {
      downlinkMax = navigator.connection.downlinkMax;
    }
  }

  console.log(
    `Current connection type: ${connectionType} (downlink max: ${downlinkMax})`,
  );
}

logConnectionType();
navigator.connection.addEventListener("change", logConnectionType);

Specifications

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
downlinkMax
61Only supported in Chrome OS
No No No No No 50 38 No 45 No 3.0

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https://developer.mozilla.org/en-US/docs/Web/API/NetworkInformation/downlinkMax