Mac battery guides

Every number in these pages is measured — on real Macs, with the method and its limits stated. Where something can't be measured honestly, the page says so instead of estimating.

Where did my battery go?

Does quitting apps actually save battery?
Mostly no — macOS handles idle apps well. But when one app is the bulk of the use, quitting it is worth real minutes. How to tell which case you're in.

Health says 96% but it only lasts four hours
Health measures the size of the tank; runtime is capacity divided by consumption. The watts-to-hours table, and the three cases where the battery really is at fault.

Overnight and sleep

Why does my Mac lose battery in sleep?
About a percentage point an hour is normal. Above that, something is waking it — and the arithmetic to tell one from the other.

Who wakes your Mac at night? A study
124 wake-ups over six nights, every one silent, median 31 seconds — and the services that asked. The biggest requester wasn't the search indexer.

Charging and power

Mac says "Charging On Hold"
It's deliberate, not broken. Every status string decoded, how to charge to full now — and the one case no status string covers.

Updates

Battery worse after the macOS 27 update?
The first days are partly expected while the system rebuilds its indexes. How to tell settling from an app that broke.

Choosing an app

The best Mac battery apps, sorted by the job
Four different jobs wear the name "battery app". Honest picks for each — including the two where the answer isn't ours.

Head to head: WattMate and Juicy · WattMate and AlDente · WattMate and coconutBattery

How the measuring works

How we count
The instruments, the arithmetic and every limitation we know about — including the numbers we refuse to print because they can't be measured honestly.