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web api instance property

NetworkInformation: downlinkMax property

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Limited availability Available in workers

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

Value

A number 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

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.