In networking and internet communication, ports play a key role in how devices and applications communicate. Think of a port as a virtual doorway that lets data pass between your device and the internet. Each service on your computer or server typically uses a specific port to send and receive data. Here’s a friendly guide to 50 common ports you should know about, whether you’re setting up a server, troubleshooting a network, or just curious about how the internet works.
| Port Number | Protocol | Description |
|---|---|---|
| 20 | FTP (File Transfer Protocol) | Used for FTP data transfer. |
| 21 | FTP (File Transfer Protocol) | Used for FTP commands. |
| 22 | SSH (Secure Shell) | Secure remote login and file transfer. |
| 23 | Telnet | Older protocol for remote access (not secure). |
| 25 | SMTP (Simple Mail Transfer Protocol) | Used for sending emails between mail servers. |
| 53 | DNS (Domain Name System) | Resolves domain names to IP addresses. |
| 67 | DHCP (Dynamic Host Configuration Protocol) | Server-side for assigning IP addresses. |
| 68 | DHCP (Dynamic Host Configuration Protocol) | Client-side for receiving IP addresses. |
| 80 | HTTP (Hypertext Transfer Protocol) | Standard protocol for browsing websites. |
| 110 | POP3 (Post Office Protocol v3) | Used by email clients to receive email. |
| 143 | IMAP (Internet Message Access Protocol) | Used by email clients to retrieve emails, more modern than POP3. |
| 161 | SNMP (Simple Network Management Protocol) | Used for managing network devices like routers and switches. |
| 443 | HTTPS (Hypertext Transfer Protocol Secure) | Secure version of HTTP, used for encrypted web browsing. |
| 465 | SMTP Secure (SMTPS) | Secure version of SMTP for sending encrypted emails. |
| 587 | SMTP (Simple Mail Transfer Protocol) | Used for sending emails securely (typically over TLS). |
| 993 | IMAPS (IMAP Secure) | Secure version of IMAP for retrieving emails. |
| 995 | POP3S (POP3 Secure) | Secure version of POP3 for retrieving emails. |
| 1080 | SOCKS Proxy | Used for proxy connections (handling requests for network traffic). |
| 1433 | Microsoft SQL Server | Default port for Microsoft SQL Server database connections. |
| 1434 | Microsoft SQL Server Resolution Service | Used by Microsoft SQL Server for discovering SQL servers. |
| 1500 | RSH (Remote Shell) | An older, less secure protocol for remote command execution. |
| 1701 | L2TP (Layer 2 Tunneling Protocol) | VPN protocol used for secure connections. |
| 1723 | PPTP (Point-to-Point Tunneling Protocol) | Used for VPNs, offering a basic level of security. |
| 1812 | RADIUS Authentication | Used for network access authentication, commonly in Wi-Fi and VPN setups. |
| 1813 | RADIUS Accounting | Used for tracking user activity and data usage on network devices. |
| 2049 | NFS (Network File System) | Used for file sharing over a network in UNIX/Linux systems. |
| 3306 | MySQL | Default port for MySQL database connections. |
| 3389 | RDP (Remote Desktop Protocol) | Used for remote desktop access to Windows systems. |
| 3690 | SVN (Subversion) | Used for version control with the SVN system. |
| 4333 | PostgreSQL | Default port for PostgreSQL database connections. |
| 5432 | PostgreSQL | Default port for PostgreSQL database connections (alternate). |
| 5900 | VNC (Virtual Network Computing) | Used for remote desktop sharing. |
| 6379 | Redis | Default port for Redis database server. |
| 8080 | HTTP Alternate | Alternative to port 80 for web traffic, often used for web apps and proxies. |
| 8081 | HTTP Alternate | Another alternative HTTP port commonly used for proxy servers. |
| 8443 | HTTPS Alternate | Used for HTTPS traffic, an alternative to port 443. |
| 8888 | HTTP Alternate | Often used by web servers for development or proxy services. |
| 9200 | Elasticsearch | Default port for Elasticsearch services. |
| 9300 | Elasticsearch | Used for communication between Elasticsearch nodes in a cluster. |
| 10000 | Webmin | Web-based interface for system administration on UNIX/Linux systems. |
| 11211 | Memcached | Default port for the Memcached distributed memory caching system. |
| 12000 | Rsync | Used for remote file synchronization. |
| 14345 | Microsoft RPC | Used by Microsoft for remote procedure calls (RPC). |
| 18000 | Dropbox | Used by Dropbox for file syncing and sharing. |
| 20000 | Webmin | Used for the Webmin administration interface on UNIX/Linux systems. |
| 2222 | SSH Alternative | Used for SSH access, sometimes as an alternative to port 22. |
| 33060 | MySQL X Protocol | Used for MySQL database client connections over X protocol. |
| 3333 | DCC (Direct Client-to-Client) | Used for direct file transfers in IRC (Internet Relay Chat). |
| 54321 | ADB (Android Debug Bridge) | Used for debugging Android devices. |
| 5901 | VNC Secure | Used for secure VNC remote desktop connections. |
This list covers many common ports that help maintain smooth operation in networks, from file sharing and web browsing to secure remote connections and email services. Knowing which ports are being used for different services can also help in troubleshooting network issues or configuring firewalls.