Skip to content

How to find the process that is using a port

Sometimes when developing multiple applications at once, or trying out demos, I end up with multiple programs running on different ports on my computer: 3000, 3001, 1313, and so on.

If I don’t pay close attention, I might forget which application is running on a specific port.

How can we determine which program is listening on a port?

The lsof command helps us do that!

Running

lsof -i :1313

Will tell me the command that’s currently listening on port 1313:

COMMAND  PID   USER   FD   TYPE             DEVICE SIZE/OFF NODE NAME
hugo    8698 fla 4764u  IPv4 0xc72ca30d18e45ef9      0t0  TCP localhost:bmc_patroldb (LISTEN)

In this case it’s the hugo command, with PID 8698.

If I want to terminate that program, I can just run kill 8698.


→ Get my Linux Command Line Handbook

download all my books for free

  • javascript handbook
  • typescript handbook
  • css handbook
  • node.js handbook
  • astro handbook
  • html handbook
  • next.js pages router handbook
  • alpine.js handbook
  • htmx handbook
  • react handbook
  • sql handbook
  • git cheat sheet
  • laravel handbook
  • express handbook
  • swift handbook
  • go handbook
  • php handbook
  • python handbook
  • cli handbook
  • c handbook

subscribe to my newsletter to get them

Terms: by subscribing to the newsletter you agree the following terms and conditions and privacy policy. The aim of the newsletter is to keep you up to date about new tutorials, new book releases or courses organized by Flavio. If you wish to unsubscribe from the newsletter, you can click the unsubscribe link that's present at the bottom of each email, anytime. I will not communicate/spread/publish or otherwise give away your address. Your email address is the only personal information collected, and it's only collected for the primary purpose of keeping you informed through the newsletter. It's stored in a secure server based in the EU. You can contact Flavio by emailing flavio@flaviocopes.com. These terms and conditions are governed by the laws in force in Italy and you unconditionally submit to the jurisdiction of the courts of Italy.

Related posts about cli: