MacBook battery calibration FAQ: My MacBook battery life seems reduced, is there something I can do to improve my MacBook battery life? (Also written as, "Can I calibrate my MacBook battery?", or, "How do I calibrate my MacBook battery for better battery life/performance?")
I'm currently in the process of switching from my older model MacBook Pro to a new MacBook Air, and in the process I've been testing my MacBook Pro battery life. Last week I ran an informal "MacBook battery calibration" experiment, and the results were terrific. Given those results, I thought I'd share the steps to calibrate a MacBook battery.
How to calibrate a MacBook battery (MacBook, MacBook Pro, MacBook Air)
The process to calibrate a MacBook battery is simple, but you'll need to do this when you won't need to use your MacBook for a few hours. Here is the step by step MacBook battery calibration process, based on notes from Apple, with my own comments and experience added in.
1) Fully charge your MacBook battery
If your MacBook battery is not already fully charged, charge it now. Plug in the power adapter, and completely charge the battery. The light on the MacBook power connector will turn to green, and the menu bar indicator will show the battery is fully charged.
2) Keep the battery charged for two hours
Now let your MacBook battery rest in this fully-charged state for at least two hours. You can use your MacBook if desired, but keep the power adapter plugged in.
3) Drain your MacBook battery
Disconnect the power adapter from your MacBook and run the computer on battery power. When your MacBook battery gets very low, the low battery warning dialog will appear on the screen. As you get to this stage, make sure you save your work (if needed).
4) Let your MacBook go to sleep
Very soon your MacBook will automatically go to sleep. Again, be sure to save your work as needed, and continue using your MacBook. When your MacBook battery gets very low your MacBook will automatically go to sleep. (You're probably best off just browsing the internet at this point, or doing anything else that is read-only.)
5) Leave your MacBook turned off
After your MacBook automatically goes to sleep, close the lid and let it sleep for five hours or more.
6) Fully re-charge the MacBook battery
After waiting at least five hours, re-connect the power adapter and re-charge your MacBook battery until the light on the power cable turns green again. (Apple doesn't mention this point, but similar to Step 2 above, I'd leave the power adapter connected for at least two hours in this state.)
My MacBook battery calibration experience
I followed these steps last week to calibrate my MacBook Pro battery, but forgot to run a formal before and after test. That being said, I can objectively say that there was a big difference, as I worked at a coffee shop both days.
Before calibrating my battery, my MacBook Pro lasted less than one hour at the coffee shop. I remember being pretty disappointed with this, as I had followed my own advice on how to improve/extend MacBook battery life.
So that night I dug around until I found this MacBook battery calibration information, and followed the steps shown above. I didn't follow Step 1 and 2 above, as I had already done those, so I started at Step 3.
Again, I don't know the exact numbers, but my MacBook battery life was closer to two hours on this second day, and was definitely longer than ninety minutes. I do know that much, just based on the time I arrived and later met up with a friend.
How often to calibrate your MacBook battery
Apple recommends that you calibrate your MacBook battery every month. Honestly, I don't remember that I'll remember to do it that often myself, but after seeing my old MacBook Pro battery barely last an hour these days, I'll definitely do it as often as I can.
More MacBook battery calibration tips and tricks
I hope this tip on how to calibrate a MacBook battery has been helpful. If you'd like any more information, I've written several related MacBook battery life articles, including these articles:
- How I extend my MacBook battery life
- Improve your MacBook battery life (2011 update)
- Apple reduces MacBook battery life claims
- How to improve iPhone battery life
If none of these Apple/MacBook battery life tips are helpful, just leave a note in the Comments section below, and I'll see what else I can do.