What is Portero?

Portero is a free, open source Mac app that shows every open port on your machine and the process behind it. Instead of digging through terminal output, you get a clear, live overview of what's listening—whether it's a dev server, a database, or something you forgot was still running. It also lets you kill processes on busy ports, fix "address already in use" errors, and block ports using the built-in macOS firewall.

Who it's for

• Developers who run multiple local servers and need to quickly see what's occupying a port
• DevOps and sysadmins who troubleshoot network issues and want to inspect listening sockets without memorizing terminal commands
• macOS power users who prefer a visual interface over lsof and ps for managing ports and firewall rules

Key features

Live overview

Every listening TCP and UDP port is displayed with its process, PID, address, user, and start time. The list auto-refreshes, so you always see the current state of your machine.

Plain words

Instead of cryptic process names, Portero translates them into readable labels like "Vite dev server" or "PostgreSQL database". Hundreds of processes and ports are recognized out of the box.

One-click kill

You can gracefully stop or force kill a process—or many at once—with a clear confirmation dialog. No accidental terminations.

Port blocking

Block inbound or outbound traffic on any port using the built-in macOS firewall. Portero writes rules into a dedicated anchor, leaving your system files untouched.

What stands out

Portero gives you a clear view of everything running on your machine, so you always know what's using each port and can stop what you don't need.

This isn't just a port scanner. Portero combines live monitoring, plain-language explanations, and direct actions—kill, block, or open in browser—all in one native Mac app. It's built on Rust and uses the same terminal tools you'd reach for (lsof, ps, pfctl), but wraps them in a clean interface that saves you time. The app also detects port conflicts before you hit the "address already in use" error, and lets you star important processes so they can't be killed accidentally.

Worth checking out if…

You work with local servers, APIs, or databases on macOS and want a faster way to see what's listening, kill stuck processes, or block ports without touching the terminal. Portero is free, open source, and runs on both Apple Silicon and Intel Macs.