How to force quite an app on mac when frozen

If the normal Force Quit window does not work, Terminal can directly stop the frozen app through macOS command lines. This method is more advanced in order to force quite an app on Mac when frozen, but it is very effective for stubborn apps that refuse to close or stay stuck in the background. It is also useful when the Dock, Finder, or Apple menu becomes slow or unresponsive.

First, go to Applications → Utilities → Terminal.

Now, find the App Name. You need the exact app name before using the command. Make sure the spelling matches the app name exactly.

In Terminal, type: 

killall AppName

Then press Enter.

The frozen app should close immediately.

P.S. Some apps require administrator permission.

sudo killall AppName

Press Enter and type the Mac password when asked. The password will not appear on screen while typing. This is normal.

Using Terminal is one of the most powerful ways to force quit a frozen app on Mac. The killall command is usually enough for most situations, while kill -9 can stop deeply stuck processes that ignore normal force quit methods. Although this method is more technical than the Apple menu or Activity Monitor, it can quickly solve serious app freezing problems when other options fail.