Portero

Portero is a free, open-source port management application for macOS that displays all listening TCP and UDP ports, identifying which processes use each port and enabling users to manage or terminate them. Live port monitoring provides a real-time overview of listening ports with process details, PIDs, addresses, and start times, and plain language explanations recognize hundreds of processes and ports with user-friendly descriptions rather than technical jargon. Process management offers one-click graceful stop or force-quit with protections for starred favorites, firewall integration provides built-in port blocking using macOS's native firewall, conflict detection alerts when multiple processes attempt to use the same port, and browser integration offers direct links to open HTTP services.