What Is CPU Usage?

Learn what is meant by high CPU usage

The Central Processing Unit (CPU) is the "brain" of your computer and processes tasks required of all of the applications you're running. That includes active programs, background tasks, and operating system services.

You can see CPU usage in Activity Monitor on the Mac (image below). The Task Manager on Windows performs the same function.

Activity Monitor running on a Mac.

CPU usage is the percentage of the total CPU capacity you're using at any given time. Older computers used to have one CPU which could only handle processing a single task at a time. However, modern computers have CPUs with multiple "cores." These are processors with multiple internal processors, each of which can handle multiple tasks simultaneously.

What Does CPU Usage Mean?

When you view details about the CPU usage on your computer, you'll see a percentage value that represents "percent utilization." It's how much of your total CPU's processing power is currently being utilized.

You'll also see information such as the CPU's current processing speed, the number of processes and threads running, and more.

CPU usage percentage can vary significantly depending on what you're doing with your computer. When the computer first boots, many programs and processes start up, and CPU usage will likely remain close to 100% until the computer is fully booted. When you're typing a document or reading a web page during regular operation, CPU usage might remain between 1% to 5%.

Save a file or launch a new program, and you'll see the CPU usage increase from 50% to 100% until that task completes.

What Is Too High CPU Usage?

If the CPU usage is high for short periods, there is no such thing as too-high usage. That's because 100% of the CPU may be required to perform specific tasks. However, that high utilization typically drops to "normal" levels.

When your CPU usage in the Task Manager or Activity Monitor remains higher than 10% to 30% for an extended period, it could indicate you have a lot of applications running in the background all the time. Common applications which might run in the background and increase your CPU usage include:

You can see all active processes running in the background in the Task Manager or Activity Monitor. On Windows, you can also see what software launches automatically by checking the startup folder.

You can reduce your overall CPU usage by removing anything mentioned above. It's as simple as installing a less CPU-intensive antivirus program, turning off software settings to auto-update, or uninstalling software like iTunes or an FTP server.

What Is a Good CPU Usage?

Normal CPU usage when you aren't running any software or loading web pages is around 1% to 5%. The following activities may create the following CPU levels. These are all considered "good" CPU usage so long as you know the activity causing it.

  • Using a program with a lot of activity like lightweight games: 10% to 30%
  • Streaming video on Netflix or YouTube: 5% to 20%
  • Playing demanding computer games: 50% to 70%
  • Booting up your computer or launching a new program: 80% to 100%

If you aren't doing anything on your computer or didn't task your computer with doing something intensive, and you can see your CPU is constantly staying above 10%, you'll need to troubleshoot your CPU usage issue. First, check if Windows is running any updates. Then, use Task Manager or Activity Monitor to sort CPU usage by process to track down which service or program may be causing the problem.

  • How do I check CPU usage on my Chromebook?

    To check CPU usage on a Chromebook, open Google Chrome, select the three-dot menu, then choose More tools > Task manager. To view all Chromebook system specs, open Chrome and enter chrome://system in the URL bar.

  • How do I check CPU usage on Linux?

    To check CPU usage on Linux, use the Top command. In the command line, enter $ top. CPU usage is listed under CPU statistics.

  • How do I check my CPU temperature?

    To test your CPU temperature on Windows, download and launch a free tool like SpeedFan, CPU Thermometer, or Core Temp. On a Mac, install the System Monitor menu bar application for continuous system monitoring. Also, make sure to take steps to keep your computer cool so parts don't overheat.

Was this page helpful?