Why is port 3000 still in use after I closed the terminal?

The Node/Vite/Next process may still be running in the background. Closing the terminal tab does not always stop child processes. Check with lsof or PortSnap and kill the listener explicitly.

Is kill -9 safe for freeing port 3000?

Prefer a normal kill first so the process can exit cleanly. Use kill -9 only if the process ignores SIGTERM. PortSnap’s Kill sends a confirmed stop so you see the process name and cwd first.

Can PortSnap free port 3000 without Terminal?

Yes. Open PortSnap, find 3000 in the live list, and Kill — or choose Free port… and enter 3000. You need a Harbor license after install.

How to free port 3000 on Mac

Updated 2026-09-28

Direct answer

To free port 3000 on Mac, find the process listening on TCP 3000 and stop it. With Terminal: run `lsof -iTCP:3000 -sTCP:LISTEN`, note the PID, then `kill <PID>` (or `kill -9 <PID>` if it ignores SIGTERM). With PortSnap: open the menu bar app, select port 3000, and Kill with confirmation — or use Free port… and enter 3000.

Free port 3000 with Terminal (macOS)

Open Terminal.
List the listener on 3000:
```
lsof -iTCP:3000 -sTCP:LISTEN
```
Note the PID column, then stop the process:
```
kill <PID>
```
If it does not exit:
```
kill -9 <PID>
```
Confirm the port is free by running lsof again — empty output means nothing is listening.

Tip: add -n -P to skip name lookups: lsof -nP -iTCP:3000 -sTCP:LISTEN.

Free port 3000 with PortSnap

Download PortSnap and open it from the menu bar (⌘⇧P).
Find 3000 in the live port list — or use Free port… and enter 3000.
Confirm Kill. The listener stops; your next npm run dev can bind again.
Optional: use Kill + Restart if you saved a start command for that project.

PortSnap shows process name, PID, command, and working directory so you do not kill the wrong app when two tools both want :3000. See features and pricing ($29 one-time).

When developers hit this

Create React App, Next.js, and many Node servers default to port 3000. Leaving a previous npm run dev running — or a zombie after closing a tab — causes “port already in use.” Related: fix EADDRINUSE in Node and find what’s using a port on Mac.

FAQ

Why is port 3000 still in use after I closed the terminal?: The Node/Vite/Next process may still be running in the background. Closing the terminal tab does not always stop child processes. Check with lsof or PortSnap and kill the listener explicitly.
Is kill -9 safe for freeing port 3000?: Prefer a normal kill first so the process can exit cleanly. Use kill -9 only if the process ignores SIGTERM. PortSnap’s Kill sends a confirmed stop so you see the process name and cwd first.
Can PortSnap free port 3000 without Terminal?: Yes. Open PortSnap, find 3000 in the live list, and Kill — or choose Free port… and enter 3000. You need a Harbor license after install.