What is using port 9000 on my Mac?

Port 9000 is a popular default for several tools: php-fpm, SonarQube, and MinIO all use it, and older Portainer and Xdebug 2 did too. A listener means one of these (or a dev server) is running. Run lsof -i :9000 to identify it.

Why do so many tools use port 9000?

9000 is an unassigned, easy-to-remember port in the registered range, so many projects adopt it as a default. That also means collisions are common, which is why some tools have since moved off it.

Port 9000: What's Using It and Is It Safe to Kill?

Q: Is it safe to kill a process on port 9000?

Usually yes; it's typically a local service or dev tool, not a macOS component. Identify the owner first, then kill it to free the port.

Port 9000 is a crowded default. Several unrelated tools claim it, so the first job is finding out which one is running. A listener on 9000 is almost always a local service or dev tool.

What typically listens on port 9000

php-fpm: The PHP FastCGI process manager listens on 9000 by default (some setups use a Unix socket instead).
SonarQube: The code-quality server’s web UI uses 9000.
MinIO: The S3-compatible storage server serves its API on 9000 (its console runs on 9001).
Portainer (older versions): Legacy Portainer used 9000 for its UI; current versions default to 9443 for HTTPS.
Xdebug 2: Used 9000, but Xdebug 3 moved its default to 9003 specifically to stop clashing with php-fpm.

Because so many tools pick 9000, conflicts are common. It’s in the registered range (1024-49151), so any app can bind it.

Is it safe to kill?

Usually yes. A process on 9000 is typically a local service or dev tool, not a macOS component. Identify the owner first (the command below shows it), then kill it to free the port. As always, don’t end something you still need.

Is it suspicious?

On a development machine, generally no, but because 9000 is so widely used, it’s worth confirming which tool owns it. An unfamiliar process is worth identifying. The command below names it.

How to find and free port 9000 on macOS

lsof -i :9000

The COMMAND column tells you whether it’s php-fpm, SonarQube, or something else. To free it:

kill -9 $(lsof -ti :9000)

Portie shows port 9000 with the exact app that owns it in its live list, which is especially useful here given how many tools compete for it.