How to Check Mac® System Performance

If you're looking for the source of lagging, slow opening, or other problems, or if you're just curious about how your computer is running, there are easy ways to check system performance on a Mac. 

Read here for tips to speed up your Mac.

How to check your Mac computer's performance.

Check Mac computer performance

The easiest way to check system performance on a Mac is to use the Activity Monitor. You can track five different categories of processes. To check how much storage space you have available, read here.

To access the Activity Monitor go to Finder, Applications, Utilities. Click Activity Monitor.

Choose the process category you'd like to check on. You can choose from CPU, Memory, Energy, Disk, Network, and Cache.

You can then choose how much information to display and in what format.

  • All Processes
  • All Processes Hierarchically, this allows you to see parent/child relationships in processes
  • My Processes, processes owned by your macOS® user account
  • System Processes, processes owned by macOS
  • Other User Processes, processes not owned by the root user (administrator account) or the current user
  • Active Processes
  • Inactive Processes, processes that are sleeping
  • Windowed Processes, processes that create a window for user action, usually apps
  • Selected Processes, processes that you selected in the Activity Monitor window
  • Applications in the last 8 hours, apps that have run in the last 8 hours.

What to check

If you're looking for a specific performance measure, you can find it, but there are some particular things to watch for.

What to check for computer performance.


You can sort the CPU pane by a variety of columns to see how much of the processor is being used by each application. This information can help identify processes that are affecting performance. The CPU Load graph shows the percent of capability currently being used. If the CPU Load is consistently over 60% you might want to check for hidden and background processes that are using a lot of processor space. Close or delete them if possible.


The Memory pane shows how memory is being used. The Memory Pressure graph illustrates the availability of memory. If the graph shows a lot of yellow and red, it might be time to increase the amount of RAM in your computer.


The Energy pane shows both overall energy use and the energy used by each open app. An important item to look for is apps that are preventing the computer from going to sleep in the Preventing Sleep column. If you are trying to save energy when the computer is not being used, be sure to shut down those apps that prevent sleep.


The Network pane shows how much data the computer is sending or receiving, broken down by individual applications. If you're monitoring how much data you're using, this is a good place to observe which apps are using the most data.

Monitor performance

If you prefer to monitor performance in real time, you can monitor CPU usage in the background as you work in other applications.

To open a window, choose Window, then CPU Usage.

If you would like a graph of the information in the Dock, choose View, Dock Icon, and CPU Usage.


Apple® offers a suite of performance monitors in Activity Monitor. These monitors allow you to track, and potentially tweak, your computer's performance.

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