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Port Status & Reference Guide TCP & UDP Networking Port Database

Searchable reference guide of standard TCP/UDP ports, service protocol definitions and security recommendations.

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Port 21 / TCPFTP
Remote Access

File Transfer Protocol for transferring files between host and client.

🔒 Security Note: Insecure plaintext transmission. Prefer SFTP (SSH port 22).
Port 22 / TCPSSH / SFTP
Remote Access

Secure Shell for encrypted remote command line shell sessions and SFTP file transfers.

🔒 Security Note: Use key-based authentication and disable root login.
Port 25 / TCPSMTP
Email

Simple Mail Transfer Protocol for mail server-to-server routing.

🔒 Security Note: Often blocked by ISPs to prevent spam relays.
Port 53 / TCP/UDPDNS
Infrastructure

Domain Name System for resolving hostname to IP addresses.

🔒 Security Note: Ensure DNS amplification DDoS protections are enabled.
Port 80 / TCPHTTP
Web

Hypertext Transfer Protocol for unencrypted web page delivery.

🔒 Security Note: Redirect all HTTP traffic to HTTPS (port 443).
Port 110 / TCPPOP3
Email

Post Office Protocol for retrieving email from mail servers.

🔒 Security Note: Prefer POP3S (port 995 with SSL/TLS encryption).
Port 143 / TCPIMAP
Email

Internet Message Access Protocol for syncing mailbox folders across devices.

🔒 Security Note: Prefer IMAPS (port 993 with SSL/TLS encryption).
Port 443 / TCPHTTPS
Web

Hypertext Transfer Protocol Secure (TLS/SSL encrypted web traffic).

🔒 Security Note: Standard secure port for modern web traffic.
Port 465 / TCPSMTPS
Email

SMTP over SSL/TLS for secure mail submission.

🔒 Security Note: Recommended secure SMTP port alongside 587.
Port 1433 / TCPMS SQL Server
Database

Microsoft SQL Server database engine listener.

🔒 Security Note: Do not expose directly to public internet; restrict via firewall/VPC.
Port 3306 / TCPMySQL / MariaDB
Database

MySQL and MariaDB relational database server listener.

🔒 Security Note: Bind to 127.0.0.1 or internal private subnet.
Port 3389 / TCP/UDPRDP
Remote Access

Remote Desktop Protocol for graphical Windows Desktop administration.

🔒 Security Note: High target for brute-force ransomware attacks. Require VPN or Bastion.
Port 5432 / TCPPostgreSQL
Database

PostgreSQL object-relational database server listener.

🔒 Security Note: Configure pg_hba.conf for strict IP restriction.
Port 6379 / TCPRedis
Database

In-memory key-value data store and cache.

🔒 Security Note: Default installation lacks password authentication. Never expose to public internet.
Port 8080 / TCPHTTP Alternate / Proxy
Web

Common alternate port for web dev servers (Vite, Next.js) and proxy servers.

🔒 Security Note: Check dev server configuration before deploying to production.
Port 27017 / TCPMongoDB
Database

MongoDB NoSQL database engine default instance.

🔒 Security Note: Enable MongoDB authentication and TLS.