Your files stay on your device

Battery status test

See your battery level and whether it is charging.

Read the battery

One press reads level, charging state, and the browser's time estimates. No reading happens on load: the battery API is a known fingerprinting vector, so it stays off until you ask.

How this test works
  • navigator.getBattery exists only in Chromium-derived browsers (and is being replaced by the Battery Status OS API elsewhere). Absent API: the page says so and stops; it never guesses a percentage.
  • Updates arrive via the manager's events, and only while the tab is visible; the route pauses its listeners on visibilitychange so a backgrounded page does not keep waking the battery API.
  • Battery level plus charging state is a known fingerprinting vector; this page reads it only after you press Read, keeps it in this tab's memory, and ships no persistence.
Paste, drop, or type to begin. Everything stays on this device.