This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.

Indicates the current battery charge level as a value between 0.0 and 1.0.


var level = battery.level

On return, level is a number representing the system's battery charge level scaled to a value between 0.0 and 1.0. A value of 0 means the battery, which is a BatteryManager object, is empty and the system is about to be suspended. A value of 1.0 means the battery is full. A value of 1.0 is also returned if the implementation isn't able to determine the battery charge level or if the system is not battery-powered.


HTML Content

<div id="level">(battery level unknown)</div>

JavaScript Content

navigator.getBattery().then(function(battery) {

    var level = battery.level;

    document.querySelector('#level').textContent = level;


Specification Status Comment
Battery Status API Candidate Recommendation Initial definition

Browser compatibility

BCD tables only load in the browser

See also