Common Ports Reference

Common network port numbers and service reference.

Network ports are virtual endpoints that enable different services to communicate over TCP/IP. Our common ports reference lists well-known port numbers and their associated services, from HTTP (80) and HTTPS (443) to SSH (22), MySQL (3306), and PostgreSQL (5432).
20,21FTP
22SSH
23Telnet
25SMTP
53DNS
80HTTP
110POP3
143IMAP
443HTTPS
587SMTP (TLS)
993IMAPS
995POP3S
3306MySQL
3389RDP
5432PostgreSQL
6379Redis
27017MongoDB
In Action

Ports Reference in action

You are configuring a firewall and the wizard asks which port your database needs. Instead of searching, glance at the table: PostgreSQL is 5432, MySQL is 3306. Keeping this reference open during server setup saves the constant back-and-forth of searching.

Frequently Asked Questions

What is the difference between TCP and UDP ports?

TCP ports provide reliable, connection-oriented communication with data ordering and error checking, used by services like HTTP (80), HTTPS (443), and SMTP (25). UDP ports are connectionless and faster, used by DNS (53) and streaming. The port numbers come from the same range of 0-65535, but the protocol behavior is different.

How do I check if a port is open?

You can use the command "telnet host port" or "nc -zv host port" from a terminal. Many network tools and online port checkers can verify reachability for you. Keep in mind that firewalls and ISP restrictions may block ports even when the remote service is running.

What is the port number for HTTP and HTTPS?

HTTP uses port 80 and HTTPS uses port 443 by default. Browsers assume these ports when you type a URL, which is why you rarely see them in the address bar.

Which ports should I leave open on my server?

Open only what your services need: typically 22 (SSH), 80 (HTTP), and 443 (HTTPS). Everything else — MySQL 3306, Redis 6379, RDP 3389 — should be bound to localhost or protected by firewall rules, never exposed directly.

What is the difference between a port and a protocol?

A port is a number that identifies a service endpoint (80 for HTTP). A protocol is the set of rules for how data is exchanged (HTTP itself). One port can serve one protocol at a time; some protocols have default ports registered with IANA.