Complete reference of common TCP and UDP port numbers with service descriptions. Search by port number or service name.
| Port | Protocol | Service | Description |
|---|
Network ports are virtual endpoints for communication in networking. They allow a single IP address to host multiple services. Port numbers range from 0 to 65535 and are divided into three categories: Well-Known Ports (0-1023), Registered Ports (1024-49151), and Dynamic/Ephemeral Ports (49152-65535).
| Range | Name | Purpose |
|---|---|---|
| 0-1023 | Well-Known | Standard services (HTTP, SSH, DNS) |
| 1024-49151 | Registered | Applications (MySQL, PostgreSQL) |
| 49152-65535 | Dynamic | Temporary client connections |
Best practice is to block all ports by default and only open what's needed. Common ports to keep open for web servers: 80 (HTTP), 443 (HTTPS), 22 (SSH). Block dangerous ports like 23 (Telnet), 3389 (RDP), and 445 (SMB) from external access.