Port Killer for Windows

Port 3000 already in use on localhost? Put the port on a Stream Deck key. It shows which program holds the port, and two presses kill that program and everything it started. Clears EADDRINUSE for Node.js, Vite, Python, Java or any other local dev server on Windows, without netstat or Task Manager.

Features

Port Watch: one key per port. Green when the port is free; red with the program's name and PID when something is listening on it (IPv4 and IPv6)

Two presses to kill the process on that port: the first asks "STOP?" and a second within 2 seconds confirms. A single press never stops anything

Stops the whole process tree, so watchers and child processes cannot keep holding the port

Checks the port again just before stopping and stops nothing if another program has taken it

Never stops Windows system processes (System, svchost, services, lsass, wininit, csrss, smss and others), the Stream Deck app or itself

Dev Ports: shows how many of your dev ports are in use (by default 3000-3010, 4200, 5000, 5173, 8000, 8080, 8888, or your own list). Press to step through them. It never stops anything

English and Japanese

Privacy

Runs entirely on your PC. No account, no online service, no telemetry.

Uses the Windows tools netstat, tasklist and taskkill with the Stream Deck app's permissions and never asks for administrator rights, so it cannot stop a server started as administrator.

Requirements

Windows 10 or later, Stream Deck app 6.9 or later

Idea or bug? Use the Support link. Every message is read.

First release with two actions. Port Watch: shows whether a TCP port is free or which program listens on it (name and PID); press twice within 2 seconds to stop that program and every program it started. Windows' own processes and the Stream Deck app are never stopped. Dev Ports: counts how many of your development ports are in use; press to see them one by one. English and Japanese.