See your device battery percentage, charging status, and estimated time remaining. Free browser battery detector.
The Battery Status API (available in Chrome and Edge) allows websites to read your device's battery level and charging state. This can be used to optimize web app behavior — for example, reducing animations or sync frequency when battery is low.
Firefox removed support for the Battery API due to privacy concerns, as it could be used as a fingerprinting vector. Safari never implemented it.
The Battery Status API is supported in Chrome and Edge. Firefox removed support due to privacy concerns because battery level can be used as a fingerprinting vector. Safari has never implemented it. You will see N/A on unsupported browsers.
Reduce screen brightness which is the largest power draw. Enable battery saver mode below 20%. Keep battery between 20-80% for long-term health. Close background apps and use dark mode on OLED screens. Avoid heat by not blocking your laptop ventilation.