DeprecatedThis feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.
The Battery Status API, more often referred to as the Battery API, provides information about the system's battery charge level and lets you be notified by events that are sent when the battery level or charging status change. This can be used to adjust your app's resource usage to reduce battery drain when the battery is low, or to save changes before the battery runs out in order to prevent data loss.
The Battery Status API extends window.navigator with a navigator.getBattery() method returning a battery promise, which is resolved in a BatteryManager object providing also some new events you can handle to monitor the battery status.
Example
In this example, we watch for changes both to the charging status (whether or not we're plugged in and charging) and for changes to the battery level and timing. This is done by listening for the chargingchange, levelchange, chargingtimechange, dischargingtimechange events.
navigator.getBattery().then(function(battery) {
function updateAllBatteryInfo(){
updateChargeInfo();
updateLevelInfo();
updateChargingInfo();
updateDischargingInfo();
}
updateAllBatteryInfo();
battery.addEventListener('chargingchange', function(){
updateChargeInfo();
});
function updateChargeInfo(){
console.log("Battery charging? "
+ (battery.charging ? "Yes" : "No"));
}
battery.addEventListener('levelchange', function(){
updateLevelInfo();
});
function updateLevelInfo(){
console.log("Battery level: "
+ battery.level * 100 + "%");
}
battery.addEventListener('chargingtimechange', function(){
updateChargingInfo();
});
function updateChargingInfo(){
console.log("Battery charging time: "
+ battery.chargingTime + " seconds");
}
battery.addEventListener('dischargingtimechange', function(){
updateDischargingInfo();
});
function updateDischargingInfo(){
console.log("Battery discharging time: "
+ battery.dischargingTime + " seconds");
}
});
See also the example in the specification.
Specifications
| Specification | Status | Comment |
|---|---|---|
| Battery Status API | Candidate Recommendation | Initial definition. |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for | |
| Chrome
Full support 38 |
Edge
Full support 79 |
Firefox No support 16 — 52 No support 16 — 52 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz Full support 52 Notes' Disabled by default in Firefox 10, but can be enabled setting the preference Notes' From this version onwards, |
IE
No support No |
Opera
Full support 25 |
Safari
No support No |
WebView Android
Full support 40 |
Chrome Android Full support 38 Full support 38 Notes' Values for |
Firefox Android No support 10 — 16 No support 10 — 16 Prefixed' Implemented with the vendor prefix: moz No support 16 — 52 Notes' Disabled by default in Firefox 10.0, but can be enabled setting the preference |
Opera Android
Full support 25 |
Safari iOS
No support ? — ? |
Samsung Internet Android Full support 3.0 Full support 3.0 Notes' Values for |
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
Battery Status API by Mozilla Contributors is licensed under CC-BY-SA 2.5.
