Skip to content

Well-Known Ports Reference — TCP and UDP Port Numbers for Common Services






Well-Known Ports Reference — TCP and UDP Port Numbers for Common Services


🔌 Well-Known Ports Reference

TCP and UDP port numbers for common services. Search by port number, service name, or use case. Includes diagnostic commands.

Diagnostic Commands

Check who’s listening on a port
ss -tlnp sport = :PORT
lsof -i :PORT
netstat -tlnp | grep PORT

Check if port is open on remote host
nc -zv host PORT
telnet host PORT
curl -v telnet://host:PORT

Scan for open ports (nmap)
nmap -p 1-1024 host
nmap -sU -p 53,67,123 host  # UDP
nmap -p- host  # All 65535 ports

Show all listening sockets
ss -tlnp     # TCP listening
ss -ulnp     # UDP listening
ss -tlnp6    # IPv6 only


Port Proto Service Description Category



Founded

2023 in London, UK

Contact

hello@releaserun.com