# How to quit an app that is using too much CPU > Select the app in Activity Monitor, click the Stop button and choose Quit or Force Quit. What each does, and why not to force quit casually. Canonical: https://www.notchstar.com/tips/quit-an-app-in-activity-monitor/ Last updated: 2026-11-04 Published 2026-11-04. Open Activity Monitor, select the app or process, click the Stop button in the upper left corner, and choose Quit. Choose Force Quit only if Quit does not work. Apple says Quit is the safe choice, because it only quits when doing so will not cause data loss. ## Steps 1. Open **Activity Monitor**. 2. Select the app or process in the **Process Name** list. Apple says an unresponsive process is marked "(Not Responding)" and appears red. 3. Click the **Stop** button in the upper left corner of the window. 4. Choose **Quit** or **Force Quit**. ## Quit or Force Quit - **Quit** works like choosing File then Quit inside the app. The process quits only when it is safe, so it will not quit if that could cause data loss or interfere with another app. - **Force Quit** quits the process immediately. Apple warns that open files may lose data, and other apps or processes that use it could have problems. Try Quit first. Give it a short wait, because an app that is saving can take a moment. Use Force Quit when an app has stopped responding. ## Find the right one Type the name in the search field, or sort the list by clicking a column heading such as CPU. To check whether another process depends on the one you are about to quit, choose **View > All Processes, Hierarchically**. ## Processes you do not own Apple says that if you try to quit a process you do not own, you may need to authenticate as an administrator. Do not quit a macOS system process unless you know what it does. If you are unsure, restart the Mac instead. ## Why it was busy Before you quit, note whether the CPU use was normal for the work you were doing. A video export keeps the processor busy and is not a fault. See [how to check CPU and memory use](https://www.notchstar.com/tips/check-cpu-and-memory-use-on-mac/). If battery is the concern, [the energy tip](https://www.notchstar.com/tips/see-which-app-uses-the-most-energy-on-mac/) helps you sort by impact. ## NotchStar's gauges NotchStar's [System tool](https://www.notchstar.com/features/system-stats/) shows CPU and memory totals, so a ring that stays orange or red tells you to open Activity Monitor. It does not list or quit processes. It shows totals only, so the quitting itself happens in Activity Monitor. ## Quick answers. ### What is the difference between Quit and Force Quit? Apple says Quit works like choosing File > Quit and only quits when it is safe, while Force Quit quits the process immediately and open files may lose data. ## Keep reading. - [CPU, memory, disk, battery and network](https://www.notchstar.com/features/system-stats/): Live CPU, memory, disk, battery and network speed gauges in your Mac notch. Sampling only runs while the tab is open, so it stays light. - [How to check CPU and memory use on a Mac](https://www.notchstar.com/tips/check-cpu-and-memory-use-on-mac/): Open Activity Monitor and click CPU or Memory to see what is using your processor and RAM, and how to read memory pressure. - [How to see which app uses the most energy on a Mac](https://www.notchstar.com/tips/see-which-app-uses-the-most-energy-on-mac/): Open Activity Monitor, click Energy, and sort by Energy Impact or 12 hr Power to find the apps draining your battery, and spot apps keeping the Mac awake. - [How to check your Mac battery health](https://www.notchstar.com/tips/check-mac-battery-health/): Open System Settings, Battery, and click the Info button beside Battery Health to see condition and maximum capacity. Also charge and longevity options. ## More in System and battery. - [How to check CPU and memory use on a Mac](https://www.notchstar.com/tips/check-cpu-and-memory-use-on-mac/): Open Activity Monitor and click CPU or Memory to see what is using your processor and RAM, and how to read memory pressure. - [How to check your Mac battery health](https://www.notchstar.com/tips/check-mac-battery-health/): Open System Settings, Battery, and click the Info button beside Battery Health to see condition and maximum capacity. Also charge and longevity options. - [How to see which app uses the most energy on a Mac](https://www.notchstar.com/tips/see-which-app-uses-the-most-energy-on-mac/): Open Activity Monitor, click Energy, and sort by Energy Impact or 12 hr Power to find the apps draining your battery, and spot apps keeping the Mac awake. - [How to turn on Low Power Mode on a Mac](https://www.notchstar.com/tips/turn-on-low-power-mode-on-mac/): Choose Low Power under Energy Mode in System Settings, Battery, separately for battery and power adapter. Which Macs Apple says support it.