Calibrating Your Apple Laptop Battery

It’s a good idea to recalibrate your laptop battery every month or so, especially if you rarely run it on battery power. Recalibration helps keep the onscreen battery display accurate and keeps the battery operating at maximum efficiency.

Recalibrating Instructions:

  1. Plug in your power adapter and fully charge your battery (till the plug turns green). Leave it plugged in for at least two additional hours.
  2. Disconnect the power adapter and start using your laptop (open several programs or play a movie to drain the battery faster).
  3. When the “battery low” message appears, save or close any important work.
  4. Continue using your computer until it goes to sleep and you can’t wake it.
  5. Allow your computer to sleep for 5 hrs or more. It may shut itself off during this time.
  6. Connect your power again and leave it connected until the battery is fully charged.

Read more from Apple

PC Users:
Calibrating the Notebook Battery in Microsoft Windows 98, ME, XP and 2000
Calibrating the Notebook Battery in Microsoft Windows 7 and Vista