How to Check CPU Usage and System Load on Mac

To check CPU usage on a Mac, open Activity Monitor from Applications, then Utilities, and click the CPU tab. Click the % CPU column to put the busiest apps at the top.

If your Mac feels warm, the fans are loud, or the battery drains quickly, one app is often working much harder than it should. Activity Monitor shows you which one.

Check CPU usage with Activity Monitor

Activity Monitor comes with every Mac:

1. Press Command + Space to open Spotlight, type Activity Monitor and press Return.
2. Click the CPU tab at the top of the window.
3. Click the % CPU column header to sort the list. The busiest apps and processes move to the top.
4. Look at the bottom of the window. % System is the part used by macOS itself, % User is the part used by your apps, and % Idle is what is left over.

Quit an app that is using too much

1. Click the app in the list.
2. Click the Stop button (the X in a circle) in the toolbar.
3. Choose Quit. If the app does not respond, choose Force Quit.

Only quit apps you recognize. Unsaved work in a force-quit app can be lost.

Watch the CPU over time

In Activity Monitor, press Command + 2 (or choose Window, then CPU History) to see a graph of recent activity for each core of the processor. Macs with Apple silicon have two kinds of cores: performance cores for heavy work, and efficiency cores for light background work. A Mac with a busy graph while you are doing nothing is a sign that something is running in the background.

Why high CPU usage drains the battery

The harder the processor works, the more power it uses. An app stuck in a busy loop can drain a MacBook battery much faster than normal use, and it makes the Mac warm and the fans loud.

Seeing your Mac's load with Tegaro

Keeping Activity Monitor open all day gets in the way. The Tegaro Power tool and the Mac load panel in the Tegaro menu-bar icon give you a quick look at how busy your Mac is, without opening another app. Both stay free after the 14-day trial.

Frequently Asked Questions