Run kill $(lsof -t -iTCP:3000 -sTCP:LISTEN) in Terminal: lsof finds the process listening on port 3000 and kill asks it to quit with SIGTERM. Portmole does the same in one click, for free: open it from the menu bar or the mole tab on the edge of your screen, find :3000 (shown with its page title, start command and project folder) and click ✕. If the process hangs, Portmole offers Force Quit, and ⌥-click forces it straight away.

Run lsof -nP -iTCP -sTCP:LISTEN in Terminal to list every process listening on a TCP port, with its name, PID and port. Portmole does this for free and keeps the list live in your menu bar: sorted into Dev, Apps and Other, searchable, and with dev servers labelled by page title, start command and project folder.

EADDRINUSE means “address already in use”: your server tried to listen on a port that another process already holds, usually an old dev server that never shut down. Stop whatever is on that port (with kill $(lsof -t -iTCP:3000 -sTCP:LISTEN), or one click on ✕ in Portmole, which is free) or start your server on a different port.

On recent versions of macOS, ports 5000 and 7000 are taken by AirPlay Receiver, which runs inside the ControlCenter process. To free them, turn off AirPlay Receiver in System Settings → General → AirDrop & Handoff, or run your app on another port. Portmole shows which process holds any port, so you can check before changing anything.

Free: every listening port in your menu bar, sorted into Dev, Apps and Other; dev servers shown by page title, start command and project folder; click to open in your browser; search; close ports in one click (✕ sends SIGTERM, Force Quit if one hangs on, ⌥-click to force); Reveal in Finder; a draggable mole tab on the screen edge (or use the menu bar); the animated mole; and the Terminal theme. Portmole Pro is a $15 one-time purchase for up to 3 Macs with lifetime updates. It adds Restart in Terminal, copy the start command, Recent (start servers again), Open a project (pick a folder and Portmole detects how to run it), Change port, live memory/CPU/power use per server, one-click cache clearing, background runs without a Terminal window, stars, the LAN badge, the dev-server count in the menu bar, and the Amber, Ice and macOS themes.

Yes. Email aryan@techynar.com within 14 days of purchase and you’ll get a full refund. The license key is deactivated when the refund is processed.

Yes, it’s safe, and no, it doesn’t need admin rights or any extra macOS permissions. Portmole is signed and notarized by Apple and has no telemetry or analytics. It only connects to your own localhost servers (to read page titles), to Dodo Payments’ license service when you activate Pro, and to a once-a-day update check that you can turn off in Settings.

Because Mac App Store apps must be sandboxed, and sandboxed apps can’t see or stop other apps’ processes, which is Portmole’s whole job. Download it directly instead: it’s signed and notarized by Apple and keeps itself up to date with built-in automatic updates (a daily check you can turn off in Settings).

Yes. Portmole is a universal app for Apple silicon and Intel Macs, and it needs macOS 14 Sonoma or later. It’s about 7 MB.