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web api instance method

Navigator: getBattery() method

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Secure context

The getBattery() method provides information about the system’s battery. It returns a battery promise, which resolves with a BatteryManager object providing some properties to get the battery status also some events you can handle to monitor the battery status. This implements the Battery Status API; see that documentation for additional details, a guide to using the API, and sample code.

Since Chrome 103, the Navigator.getBattery() method of Battery Status API only expose to secure context.

[!NOTE] Access to this feature may be controlled by the Permissions-Policy directive battery.

Syntax

getBattery()

Parameters

None.

Return value

A Promise that fulfills with a BatteryManager object which you can use to get information about the battery’s state.

Exceptions

  • NotAllowedError DOMException

  • SecurityError DOMException

    • : The User Agent does not expose battery information to insecure contexts and this method was called from an insecure context.

Examples

This example fetches the current charging state of the battery and establishes a handler for the chargingchange event, so that the charging state is recorded whenever it changes.

let batteryIsCharging = false;

navigator.getBattery().then((battery) => {
  batteryIsCharging = battery.charging;

  battery.addEventListener("chargingchange", () => {
    batteryIsCharging = battery.charging;
  });
});

For more examples and details, see Battery Status API.

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also