Common TCP/UDP Ports

Quick reference for the most frequently used TCP and UDP port numbers.

Port Ranges

RangeNameDescription
0-1023Well-Known PortsSystem/privileged services, require root
1024-49151Registered PortsRegistered with IANA for specific services
49152-65535Dynamic/PrivateEphemeral ports for client connections

Well-Known Ports (0-1023)

PortProtocolServiceDescription
20TCPFTP DataFile Transfer Protocol data channel
21TCPFTP ControlFile Transfer Protocol control channel
22TCPSSHSecure Shell remote login
23TCPTelnetTelnet remote login (insecure)
25TCPSMTPSimple Mail Transfer Protocol
53TCP/UDPDNSDomain Name System
67UDPDHCP ServerDynamic Host Configuration Protocol server
68UDPDHCP ClientDynamic Host Configuration Protocol client
69UDPTFTPTrivial File Transfer Protocol
80TCPHTTPHypertext Transfer Protocol
110TCPPOP3Post Office Protocol v3
123UDPNTPNetwork Time Protocol
143TCPIMAPInternet Message Access Protocol
161UDPSNMP AgentSimple Network Management Protocol
162UDPSNMP ManagerSNMP trap messages
443TCPHTTPSHTTP over TLS/SSL
993TCPIMAPSIMAP over TLS/SSL
995TCPPOP3SPOP3 over TLS/SSL

Registered Ports (1024-49151)

PortProtocolServiceDescription
179TCPBGPBorder Gateway Protocol
389TCPLDAPLightweight Directory Access Protocol
636TCPLDAPSLDAP over TLS/SSL
989TCPFTPS DataFTP over TLS/SSL data
990TCPFTPS ControlFTP over TLS/SSL control
1433TCPMS SQL ServerMicrosoft SQL Server
1521TCPOracle DBOracle Database
1723TCPPPTPPoint-to-Point Tunneling Protocol
3306TCPMySQLMySQL Database
3389TCPRDPRemote Desktop Protocol
5432TCPPostgreSQLPostgreSQL Database
5900TCPVNCVirtual Network Computing

Common Service Categories

Web Services
80, 8080 - HTTP
Not secure
443, 8443 - HTTPS
Secure
Email Services
25 - SMTP
Not secure
587 - SMTP (submission)
Secure
110 - POP3
Not secure
995 - POP3S
Secure
143 - IMAP
Not secure
993 - IMAPS
Secure
Remote Access
22 - SSH
Secure
23 - Telnet
Not secure
3389 - RDP
Not secure
5900+ - VNC
Not secure
Database Services
1433 - SQL Server
Not secure
1521 - Oracle
Not secure
3306 - MySQL
Not secure
5432 - PostgreSQL
Not secure

Important Security Tips

Remember These
Ports below 1024 typically require administrator privileges
HTTPS is HTTP + TLS/SSL encryption (port 443)
SSH (22) is the secure replacement for Telnet (23)
Email uses multiple ports: 25 (SMTP), 110 (POP3), 143 (IMAP)
Add 'S' suffix for secure versions: HTTPS, FTPS, IMAPS, POP3S
Database ports are often targeted by attackers - secure them well
Security Note
Many services have both secure and insecure versions. Always use the secure versions (HTTPS, SSH, FTPS, etc.) when possible, especially over untrusted networks.