TCP/UDP Port Lookup
Search the well-known ports used by mail, web, remote access, databases, Windows domains and VoIP – with protocol and firewall notes.
A searchable list of the ports an administrator actually meets – mail (25, 465, 587, 993), web, remote access, Windows domain services, databases, VPNs and monitoring – with notes on which should never be open to the internet. Type a number or a word such as mail, vpn or database.
Firewall rule of thumb
Expose only what the service needs (usually 80/443, mail ports on a mail server, and a VPN). RDP 3389, SMB 445, databases and Redis should never face the internet directly – put them behind a VPN or allow-list.
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