Top Network Ports Every IT Pro Should Remember

Network ports are like digital doorways used by applications to communicate over the internet or internal networks. Whether you’re managing servers, troubleshooting issues, or learning networking, knowing the right ports can save time and avoid headaches. Let’s walk through a complete, list of the most important and commonly used network ports.

What Are Network Ports?

A port is a number assigned to a specific process or service. For example, when you visit a website, your browser connects to port 80 or 443 behind the scenes.

Most Common and Important Network Ports

Port	Protocol/Service	Purpose
20	FTP (Data)	File Transfer Protocol (data transfer)
21	FTP (Control)	File management and login
22	SSH	Secure remote login
23	Telnet	Unsecured remote access (not recommended)
25	SMTP	Sending emails
53	DNS	Domain name resolution
67/68	DHCP	Assigning IP addresses automatically
69	TFTP	Trivial file transfers (no security)
80	HTTP	Standard web traffic (insecure)
110	POP3	Email receiving (basic)
123	NTP	Time synchronization
135	RPC	Remote procedure call for Windows services
137-139	NetBIOS	Windows file sharing and printer services
143	IMAP	Advanced email retrieval
161/162	SNMP	Network monitoring and alerts
179	BGP	Border Gateway Protocol for routers
389	LDAP	Directory services (Active Directory, etc.)
443	HTTPS	Secure web traffic
445	SMB	File sharing (Windows)
465	SMTPS	Secure email sending
514	Syslog	System logging
587	SMTP (Submission)	Sending email with authentication
636	LDAPS	Secure LDAP
989/990	FTPS	Secure FTP
993	IMAPS	Secure IMAP
995	POP3S	Secure POP3

Database Ports

Port	Database	Purpose
1433	Microsoft SQL Server	Database connections
1521	Oracle Database	Oracle listener service
3306	MySQL/MariaDB	MySQL database access
5432	PostgreSQL	PostgreSQL access
27017	MongoDB	MongoDB default port

Remote Access & Tools

Port	Service	Purpose
3389	RDP	Remote Desktop Protocol (Windows)
5800/5900	VNC	Virtual desktop control
8000	Common Dev Port	Used for web servers during testing
8080	HTTP Alternate	Common for proxy/web applications
8443	HTTPS Alternate	Secure version of 8080

Security & Monitoring

Port	Tool/Service	Purpose
514	Syslog	Remote logging
5601	Kibana	Elasticsearch interface
9200	Elasticsearch REST API	Data search and analytics
15672	RabbitMQ Management	Message queue monitoring
9090	Prometheus	Metrics collection
3000	Grafana	Dashboard and visualization

Tips to Keep in Mind

Secure the defaults: If you’re using common ports, make sure services are properly secured (e.g., SSL/TLS).
Don’t leave open ports exposed: Close or firewall unused ports to prevent unauthorized access.
Use port scanning tools: Tools like nmap help you check which ports are open on a server.

Conclusion

You don’t need to memorize every port, but keeping a list like this handy can really help with server setup, debugging, and network design. Whether you’re a sysadmin or an aspiring dev, understanding ports will level up your IT skills.