Low Power Mode on a Mac explained: what it slows and what it saves
· 5 min read
Low Power Mode makes your Mac use less energy by holding back performance, so a MacBook lasts longer on a charge and its fans stay quieter. Turn it on when you’re away from a charger and the work is light: email, writing, browsing. Leave it off for exports, builds and anything where waiting costs you more than the battery does.
What it does and doesn’t do
Apple’s summary is short: Low Power Mode reduces energy use to increase battery life. From macOS Sequoia 15.1 it also helps keep fan noise down on Macs with fans, and cuts power use on a Mac that’s always left on.
The settings pane says much the same. On a laptop with fans it reads “Your Mac will reduce energy usage to increase battery life and operate more quietly.” Without fans, it reads “Your Mac will reduce energy usage to increase battery life.”
In practice the Mac manages performance to use less energy. You notice it as slower exports, longer compiles and less headroom when many things run at once. Typing, reading and video playback usually feel the same.
It does not make the battery healthier, it doesn’t stop an app that is stuck in a loop, and it doesn’t limit one app more than another. It applies to everything.
Where to turn it on
On a Mac laptop:
- Open the Apple menu, then System Settings.
- Click Battery in the sidebar (you may need to scroll).
- Open the pop-up menu next to Low Power Mode and choose “Always,” “Only on Battery,” or “Only on Power Adapter.” The same menu turns it off again.
“Only on Battery” is the choice most people want, because the mode then switches itself off when you plug in.
Some Macs show Energy Mode instead, with an “On battery” and an “On power adapter” menu. Each offers Low Power and Automatic, plus High Power on Macs that have it, and Automatic is the default. Apple says that from macOS Sequoia 15.1 you can also pick the mode in Control Center.
On a desktop Mac, look in System Settings under Energy. Apple lists Low Power Mode for the Mac mini from 2024 on, the 2024 iMac and the Mac Studio from 2025 on. The 2023 Mac mini and 24-inch iMac get it with macOS Sequoia 15.1 or later, and the 2023 Mac Studio with 15.3 or later. On a desktop it’s aimed at quiet work and at Macs left on all the time, such as one used as a server.
High Power Mode
Some Macs offer the opposite choice. macOS describes it as “Your Mac will optimize performance to better support resource-intensive tasks. This may result in louder fan noise.” Apple says it lets the fans run faster, which can help in very heavy work such as color grading 8K video.
Apple lists it for these models:
- MacBook Pro from 2024 or later with a Pro or Max chip
- MacBook Pro from 2021 through 2023 with a Max chip
- Mac mini from 2024 or later with a Pro chip
- Mac Studio introduced in 2026
On a 14-inch MacBook Pro with an M4 Pro or M5 Pro chip, Apple recommends the 96W USB-C Power Adapter for High Power Mode while charging. To check which mode is on, click the battery (or lightning bolt) icon in the menu bar.
When to use it, and when to leave it
Turn it on for a flight, a long day away from a charger, or when the battery is already low and you need the Mac to last. It also helps when the fans are loud during easy work.
Leave it off when you export video, compile code, run a big spreadsheet or play a game, since heavy work takes longer with it on. If the Mac feels sluggish for no reason, check this setting first: a mode left on “Always” explains a Mac that suddenly feels slow.
For heat and fan noise that persist, why a Mac gets hot goes through the causes. If the Mac isn’t charging at all, see charging on hold or not charging. To have settings change when you unplug, change Mac settings automatically when you unplug the charger shows one way. What the battery health percentage means covers the other half of battery life.
When one app is the real drain
Low Power Mode slows everything to save energy. If one app is eating the battery, that’s a blunt fix. Find the app first. How to find which app is draining your MacBook battery walks through it.
Where Foreman fits
Foreman is a Task Manager for macOS. Its App History page lists what each app has used since it opened, including Energy in watt-hours, so you can sort by Energy and see what drained the battery. The totals last only while the app stays open.
For the app you find, Efficiency Mode runs it at background priority while it’s in the background and holds it to about a quarter of the processor time it would otherwise take. In front, or while it plays sound, it runs at full speed. That cuts one app down without slowing the rest of the Mac.
Foreman doesn’t switch Low Power Mode on or off, and it doesn’t show battery health or temperatures. After a 24-hour free trial it costs $12, once, for up to 3 Macs.
Questions
Does Low Power Mode make a Mac slower? Yes, when the work is heavy. It lowers performance to use less energy, so exports and builds take longer. For light tasks you rarely notice.
Where is Low Power Mode on a Mac? On a Mac laptop, open System Settings and click Battery, then use the pop-up next to Low Power Mode, or the Energy Mode menus on Macs that have High Power Mode. On a desktop Mac that supports it, it’s under Energy.
Is there Low Power Mode on a Mac mini or iMac? On recent models, yes. Apple lists the Mac mini from 2024 on and the 2024 iMac, plus the 2023 Mac mini and 24-inch iMac with macOS Sequoia 15.1 or later. It’s in System Settings under Energy, where it lowers power use and fan noise.
Does Low Power Mode save battery on a Mac? Yes. Apple describes it as reducing energy use to increase battery life. How much you gain depends on what you’re doing, so no figure is promised.