BatteryManager.level

Obsolete
This feature is obsolete.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.

Syntax

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.

Example

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;
});

Specifications

Specification Status Comment
Battery Status API Candidate Recommendation Initial definition

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidFirefox for AndroidOpera for AndroidSafari on iOSSamsung Internet
level
Deprecated
Chrome Full support 38Edge No support NoFirefox No support 16 — 52
No support 16 — 52
No support 10 — 16
Prefixed
Prefixed Implemented with the vendor prefix: moz
Full support 52
Notes Disabled
Notes Disabled by default in Firefox 10, but can be enabled setting the preference dom.battery.enabled to true. Starting with Firefox 11, mozBattery is enabled by default. The Battery API is currently supported on Android, Windows, and Linux with UPower installed. Support for MacOS is available starting with Firefox 18. Firefox also provide support for the deprecated navigator.battery.
Disabled From version 52: this feature is behind the dom.battery.enabled preference. To change preferences in Firefox, visit about:config.
Full support 52
Notes
Notes From this version onwards, the Battery Status API is only available in chrome/privileged code.
IE No support NoOpera Full support 25Safari No support NoWebView Android Full support 40Chrome Android Full support 38
Notes
Full support 38
Notes
Notes Values for BatteryManager.chargingTime and BatteryManager.dischargingTime are always equal to Infinity.
Firefox Android No support 10 — 16
Prefixed
No support 10 — 16
Prefixed
Prefixed Implemented with the vendor prefix: moz
No support 16 — 52
Notes Disabled
Notes Disabled by default in Firefox 10.0, but can be enabled setting the preference dom.battery.enabled to true. Starting with Firefox 11.0, mozBattery is enabled by default. The Battery API is currently supported on Android, Windows, and Linux with UPower installed. Support for MacOS is available starting with Gecko 18.0 (Firefox 18.0 / Thunderbird 18.0 / SeaMonkey 2.15). Firefox also provide support for the deprecated navigator.battery.
Disabled From version 16 until version 52 (exclusive): this feature is behind the dom.battery.enabled preference. To change preferences in Firefox, visit about:config.
Full support 52
Notes
Notes From this version onwards, the Battery Status API is only available in chrome/privileged code.
Opera Android Full support 25Safari iOS No support ? — ?Samsung Internet Android Full support Yes

Legend

Full support  
Full support
No support  
No support
Deprecated. Not for use in new websites.
Deprecated. Not for use in new websites.
See implementation notes.
See implementation notes.
User must explicitly enable this feature.
User must explicitly enable this feature.
Requires a vendor prefix or different name for use.
Requires a vendor prefix or different name for use.

See also

Last modified:

, by MDN contributors
Related Topics