Battery Information

Battery Information shows what your browser reports about the battery of the laptop, phone or tablet it is running on: the charge as a percentage, drawn as a battery, whether the charger is connected, and the browser’s own estimate of how long until the battery is full or how long it will last. Everything updates live, so plugging the charger in or out changes the page within a moment. It is a quick way to check that a charger or cable is actually charging — the state should switch to Charging when you plug in — or to see the battery level on a device whose own indicator is hidden, such as a kiosk or a full-screen app. A desktop computer has no battery, and browsers report that the same way as a full battery on charge; the page says so rather than guessing.

1. Open the page in Chrome, Edge, Opera or Samsung Internet.
2. Read the level and state. Plug the charger in or out and watch it change.
3. Give the time estimates a minute or two to appear; the browser needs to watch the level move first.

• Only Chromium browsers (Chrome, Edge, Opera, Samsung Internet) share battery details with pages. Firefox and Safari removed the feature because it could be used to tell visitors apart; on those, the page says it is not available.
• Browsers round the level and the time estimates, and the estimates come from how fast the level has moved recently, so they jump about when you start or stop heavy work.
• Battery health, wear, cycle count and design capacity are not available to web pages. On Windows, the command “powercfg /batteryreport” creates a full report; on a Mac, see System Settings → Battery; on Android and iPhone, the battery settings.
• A computer without a battery reports itself as full and charging, so the page cannot tell you for certain that a battery is missing.
• The battery details are read by this page in your browser and shown only to you. Nothing is sent or stored.

Open this page and plug the charger in. The state should change to Charging within a few seconds. If it stays On battery, check the cable, the socket and the charger’s power rating.

Your browser does not share it. Firefox and Safari removed the feature for privacy. Open the page in Chrome or Edge, or use your system’s battery menu.

No — browsers do not expose health or wear. Use your system’s battery settings or a battery report tool for that.

Because it has no battery, and browsers report that the same way as a full battery on charge.