Common Ports Lookup
Search common TCP and UDP ports by number or service name. Handy when you are writing firewall rules or working out what is listening on a box.
🔒 Runs entirely in your browser. Nothing you type is sent anywhere.
How to use it
Type a port number, such as 443, or part of a service name, such as database or ssh. The list filters as you type.
A note on reducing attack surface
Every open port is a door. A tidy server only listens on the ports it actually needs, and the firewall only allows those from the places that should reach them. A few that often get left exposed by mistake, and should almost never face the internet: Redis (6379), MongoDB (27017), the Docker API (2375), and database ports like MySQL (3306) and PostgreSQL (5432). Put those behind a VPN or bind them to localhost.
FAQ
Is this every port? No. There are 65,535 ports; this is a working list of the ones that come up most in self-hosting and home labs. For an authoritative list, see the IANA service name registry.
How do I see what is listening on my own server?
Use ss -tulpn on Linux. For a view from the outside, scan from another machine with nmap.