This common port numbers reference lists the well-known TCP/UDP ports used by popular protocols and services — HTTP (80), HTTPS (443), SSH (22), databases and email. Handy for firewalls, networking and server setup.
| Port | Service | Use |
|---|---|---|
| 20, 21 | FTP | File transfer |
| 22 | SSH | Secure shell / SFTP |
| 23 | Telnet | Unencrypted remote login |
| 25 | SMTP | Email sending |
| 53 | DNS | Domain name resolution |
| 67, 68 | DHCP | IP address assignment |
| 80 | HTTP | Web (unencrypted) |
| 110 | POP3 | Email retrieval |
| 143 | IMAP | Email retrieval |
| 443 | HTTPS | Web (encrypted) |
| 465, 587 | SMTPS | Secure email sending |
| 993 | IMAPS | Secure IMAP |
| 3306 | MySQL | MySQL / MariaDB database |
| 5432 | PostgreSQL | PostgreSQL database |
| 6379 | Redis | Redis cache |
| 27017 | MongoDB | MongoDB database |
| 3389 | RDP | Windows remote desktop |
| 8080 | HTTP-alt | Alternate / proxy web |
| 8443 | HTTPS-alt | Alternate secure web |