Port Reference

A short offline list of the ports that come up most often, with the service name and a note on what runs there. Search by number or name, or narrow to TCP or UDP. No lookups are made.

Ports

About this tool

A compact, offline table of the ports that come up most often when you read configs, logs and firewall rules. Each row gives the port number, whether it is TCP, UDP or both, the usual service name and a one-line note on what it carries. Search by number or name.

Questions

Is this a full list of every port?
No, it is a shortlist of the common ones. The IANA registry has thousands of assignments. This table is meant to answer the everyday question of what is probably running on a port, not to be a complete authority.
Does a port number guarantee the service?
No. A port is just a number; anything can listen on it. The service column shows the conventional assignment, so treat it as a strong hint and confirm with the process or the application config.
What is the difference between TCP and UDP for the same port?
They are separate namespaces. Port 53 is used by DNS over both, and port 123 is UDP for NTP. When a service uses both, the row lists tcp/udp, and the protocol filter matches either.
Why are some dev-server ports listed as alternatives?
Ports like 3000, 5000 and 8000 have no official service. They are shown as common development defaults because that is how they actually turn up, and the note makes clear they are conventions rather than assignments.