BatteryManager: level property

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The level read-only property of the BatteryManager interface indicates the current battery charge level as a value between 0.0 and 1.0. A value of 0.0 means the battery is empty and the system is about to be suspended. A value of 1.0 means the battery is full or the user agent is unable to report the battery status information. When its value changes, the levelchange event is fired.

Value

A number.

Examples

Getting the battery level

HTML

html
<button id="get-level">Get battery level</button>
<div id="output"></div>

JavaScript

js
const getLevel = document.querySelector("#get-level");
const output = document.querySelector("#output");

getLevel.addEventListener("click", async () => {
  if (!navigator.getBattery) {
    output.textContent = "Battery manager is unsupported";
  } else {
    const manager = await navigator.getBattery();
    const level = manager.level;
    output.textContent = `Battery level: ${level}`;
  }
});

Result

Specifications

Specification
Battery Status API
# dom-batterymanager-level

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
level

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support
No support
No support

See also