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BatteryManager: level property

The BatteryManager.level property 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

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
level 38 79 43–52 No 25 No 38 38 43–52 25 No 3.0

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/BatteryManager/level