How to kill a process in Linux: A cheatsheet (kill, killall, pkill, fuser)

Ever had a frozen application or a rogue script that just won't die? Knowing how to properly terminate a process is a fundamental skill for any Linux user, developer, or sysadmin.

This cheatsheet covers four essential commands to handle any unresponsive process: kill, killall, pkill, and the powerful fuser for network ports.

Part 1: Kill by Process ID (PID) - The Classic Way

This is the most precise method. First, you find the Process ID (PID), then you send a signal to it.

Copy-Paste Version:

First, find the Process ID (PID) of your app:

ps aux | grep 'my_process'

Then, kill the process by its PID:
Sends a "graceful shutdown" signal (SIGTERM 15)

kill PID_NUMBER

If it doesn't work, force kill the process:
Sends an "ungraceful kill" signal (SIGKILL 9)

kill -9 PID_NUMBER

Part 2: Kill by Name - The Convenient Way

These commands are perfect when you don't want to look up the PID first.

Copy-Paste Version:

Kill a process by its exact name:
Note: killall is very strict with the name

killall my_process

Force kill a process by its exact name:

killall -9 my_process

A more flexible way to kill by name (finds partial matches):

pkill -f 'my_process_or_script.py'

Part 3: Kill by Port Usage - The Network Way

Incredibly useful for web developers and sysadmins when a port is unexpectedly occupied.

Copy-Paste Version:

Find and kill the process using a specific port (e.g., 8443):
The '-k' option sends the SIGKILL signal by default

fuser -k 8443/tcp

Downloadable version:

Source & downloads:

You can find the original PNG version of this cheatsheet in the original post:

How to kill a process in Linux: A cheatsheet (kill, killall, pkill, fuser)