How to find which app is draining your MacBook battery

To find which app is draining your MacBook battery, look at how much energy each app is using right now and how much it has used since it opened. Foreman shows both: a Power usage column on its Processes page for the moment, and an Energy column on its App History page, in watt-hours, for the total. Sort by either one and the app at the top is your answer.

macOS has its own places to look too, and this post covers those first, then what to do once you have found the app.

Start with what macOS shows you

Click the battery icon in the menu bar. If one or more apps are using a lot of energy, macOS lists them there under Using Significant Energy. If it says No Apps Using Significant Energy, no single app stands out right now.

System Settings > Battery has graphs of Battery Level and Screen On Usage for the last 24 hours or the last 10 days. They tell you when the battery went down fast, such as a drop during a meeting or overnight when the Mac should have been asleep. Do not count on them to break the drain down by app: use them to find the time, then work out what was running then.

These tools are good for spotting a problem. For a ranked list of apps with figures, you need a process list.

Power usage: what is draining now

Foreman has a Power usage column on its Processes page. Click the header to sort by it. Apps are grouped with their helper processes, so a browser’s total includes its tabs and helpers, and you see the app, not twenty separate lines.

Use this when the battery is draining right now: the fan is spinning, the Mac feels warm, the percentage is falling quickly. Whatever is at the top is what is working hardest at this moment. If it is an app you are not using, that is the one to deal with.

Check the same view a minute later. A brief peak, such as an app finishing a sync, means little. An app that stays at the top and is not doing anything you asked for is a drain.

App History: what has used the most since it opened

A snapshot only shows the present. For slow drains, an app that uses a modest amount all day, the total matters more. Foreman’s App History page shows, for each app, what it has used since it opened: how long it has been open, its processor time, disk read and written, network, and Energy in watt-hours.

Sort by Energy. This answers the question “what has actually drained my battery today” better than any snapshot, because it adds up the whole time the app has been open. An app that you left open all day in the background can beat one you used hard for twenty minutes.

One limit to know about: the totals last only as long as the app stays open. When an app quits, its totals are gone, and Foreman does not keep history after that. So it is most useful for apps that have been running a long time, which is also where the slow drains are. If the battery was drained by an app that has since quit, App History will not show it.

What to do once you have found it

Match the fix to the app.

• An app you are not using. Quit it. In Foreman, End Task asks it to quit the normal way, so it can save your work. If it is hung, use Force Quit. For menu bar apps and background tools, quitting is often all it takes.
• A browser. It is usually the largest drain on a laptop. Close tabs you are not reading, especially ones that play video or run in the background, and quit it when you finish. How to tell if one browser tab is slowing down your Mac helps find the heavy one.
• An app you need open but not in use. Use Efficiency Mode. In the background, the app runs at background priority, on the efficiency cores of Apple silicon, and in short bursts, at about a quarter of the processor time it would take. In front, or while playing sound, it runs at full speed. It is remembered for that app until you turn it off. Because it lowers how much work the app does when you are not looking, it can help on battery, but how much depends on how busy the Mac is.
• A busy background process. Indexing, photo analysis and backups run in the background and can use power for a while, then stop. How to find out what’s running in the background on your Mac explains the common ones. Efficiency Mode also works on macOS’s own background processes that run under your account, such as Photos analysis (photoanalysisd), but not on ones owned by root or a system account. If a system process stays busy for hours, restart the Mac before anything else.
• Something that starts at login and sits there. Switch it off at startup, and the drain goes with it. How to stop apps opening at login on a Mac shows how.

Other things that drain a battery

Not every drain is an app. The screen is one of the biggest draws on a laptop, so a high brightness setting can matter more than most apps. External devices on USB ports, a busy Wi-Fi connection, and tasks such as video calls and video editing all draw power. If the process list shows nothing unusual and the battery still falls fast, look at those next.

Foreman does not show battery health or temperatures, so it cannot tell you how worn the battery is. For that, look in System Settings under Battery.

The short version

Check the battery menu in the menu bar first. Then sort a process list by Power usage for what is draining now, and sort App History by Energy for what has drained the most since each app opened. Quit what you are not using, trim the browser, and use Efficiency Mode for the rest.