Data lookups
Network port numbers
Which port HTTPS, SSH, SMTP, DNS and the rest listen on.
45 entries.
| Port | Protocol | Service | Notes |
|---|---|---|---|
| 20 | TCP | FTP (data) | The data channel for classic FTP. |
| 21 | TCP | FTP (control) | Unencrypted — prefer SFTP or FTPS. |
| 22 | TCP | SSH / SFTP / SCP | Secure shell and secure file transfer. |
| 23 | TCP | Telnet | Unencrypted remote shell. Obsolete; do not expose. |
| 25 | TCP | SMTP | Server-to-server mail. Often blocked by ISPs. |
| 53 | TCP/UDP | DNS | Name resolution. UDP normally, TCP for large answers. |
| 67 | UDP | DHCP (server) | Hands out IP addresses. |
| 68 | UDP | DHCP (client) | Client side of DHCP. |
| 69 | UDP | TFTP | Trivial FTP, used for network booting. |
| 80 | TCP | HTTP | Unencrypted web traffic. |
| 110 | TCP | POP3 | Legacy mail retrieval, downloads and deletes. |
| 119 | TCP | NNTP | Usenet news. |
| 123 | UDP | NTP | Clock synchronisation. |
| 135 | TCP | MS RPC | Windows RPC endpoint mapper. Never expose to the internet. |
| 137-139 | TCP/UDP | NetBIOS | Legacy Windows networking. Keep on the LAN. |
| 143 | TCP | IMAP | Mail retrieval that keeps messages on the server. |
| 161 | UDP | SNMP | Network device monitoring. |
| 162 | UDP | SNMP trap | Alerts sent from devices. |
| 389 | TCP | LDAP | Directory services. |
| 443 | TCP | HTTPS | Encrypted web traffic. Also QUIC/HTTP3 over UDP. |
| 445 | TCP | SMB | Windows file sharing. A common ransomware route — never expose. |
| 465 | TCP | SMTPS | Mail submission over implicit TLS. |
| 514 | UDP | Syslog | Remote logging. |
| 587 | TCP | SMTP submission | The correct port for sending mail with STARTTLS. |
| 636 | TCP | LDAPS | LDAP over TLS. |
| 993 | TCP | IMAPS | IMAP over TLS. |
| 995 | TCP | POP3S | POP3 over TLS. |
| 1433 | TCP | Microsoft SQL Server | Default database port. |
| 1521 | TCP | Oracle Database | Default listener port. |
| 1723 | TCP | PPTP | Obsolete VPN protocol — insecure. |
| 3128 | TCP | Squid proxy | Common HTTP proxy port. |
| 3306 | TCP | MySQL / MariaDB | Default database port. |
| 3389 | TCP | RDP | Windows Remote Desktop. Put it behind a VPN. |
| 5060 | TCP/UDP | SIP | VoIP signalling. |
| 5061 | TCP | SIP over TLS | Encrypted VoIP signalling. |
| 5432 | TCP | PostgreSQL | Default database port. |
| 5672 | TCP | AMQP / RabbitMQ | Message queuing. |
| 5900 | TCP | VNC | Remote desktop sharing. |
| 6379 | TCP | Redis | In-memory data store. Never expose unauthenticated. |
| 8080 | TCP | HTTP alternate | Development servers and proxies. |
| 8443 | TCP | HTTPS alternate | Secondary TLS port for admin panels. |
| 9000 | TCP | PHP-FPM | FastCGI process manager. |
| 9200 | TCP | Elasticsearch | Search engine HTTP API. |
| 11211 | TCP/UDP | Memcached | Cache server. Never expose to the internet. |
| 27017 | TCP | MongoDB | Default database port. |
Ports 0–1023 are "well known" and usually need admin rights to bind. Assignments are maintained by IANA.