Force Your MacBook to Only Charge up to 80 Percent (and Why You Should)

Batteries are not magic. They are chemical. And, like most things made by humans, they deteriorate over time. I don’t need to tell you this—anyone who’s owned a MacBook knows that as it ages, battery life gets worse. But what if I told you that it was possible to slow that process down?

A general advice is to only charge your devices up to 80 percent most of the time. Battery University, a consultancy that helps big companies get the most out of batteries, suggests this based on its own research. The National Renewable Energy Laboratory does the same.

But how do you actually follow this advice? The good news is that your MacBook already does this, and there’s a great free application that allows you to go even further.

built-in optimization

Your Mac is designed to only charge up to 80 percent—at least, in some circumstances. By default, Mac devices learn your charging and usage routine and optimize your battery life based on that. According to Apple, “Your Mac delays charging by more than 80 percent when it predicts you’ll be plugged in for an extended period of time, and aims to fully charge the battery before you unplug.”

What does this mean? Well, for example, if you charge your laptop overnight, your Mac will charge up to 80 percent, then wait until the morning to top off the last 20 percent. The idea is to reduce the time it takes for the battery to fully charge in such a way that you don’t even notice.

The good thing about this feature is that you don’t have to do anything to take care of your battery health. Your Mac is already doing what it can, so simply charging up to 80 percent whenever your routine suggests it won’t affect you.

(This feature is actually a macOS setting that’s on by default. You can find it in settings > Battery > battery healthWhere you can turn off this protective setting, though, you should keep reading to find out if that’s best.)

If you never want to wonder how charged your battery is, stop reading. However, if you want more control, I have some advice.

Take control with a free app

There are some potential problems with Apple’s approach. The first is that you are not in control. For example, if you wake up earlier than usual to catch a flight, you may find that your MacBook isn’t fully charged, and then on a long travel day you’re stuck with a partially charged battery.

However, the bigger issue for me is that my daily battery usage is not very regular. I do most of my work at my desk, where my computer is plugged into my monitor, which also charges it. However, I like to move around my place throughout the day, which means I unplug at random times. And sometimes I keep my laptop in my bag and work in the library or coffee shop. It’s a good idea to make sure I’m fully charged when I do this.

You get the idea: Not everyone’s daily routine is predictable. If this sounds familiar, and you want to take direct control of your MacBook charging, I recommend a free and open source app called Battery.

This application resides in your menu bar and forces your laptop to only charge up to 80 percent. However, you can allow full charging at any time by clicking the menu bar icon.

This will require a little planning and attention on your part. You have to remember to enable full charge before you need it, and turn the limit back on when you know you won’t need it.

But for someone like me, who mostly uses my MacBook at my desk, this is a way to make sure my battery stays healthy for as long as possible.