NetworkInformation.downlinkMax

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. 

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

Specification
Network Information API
# dom-networkinformation-downlinkmax

Browser compatibility

BCD tables only load in the browser