Port Number Reference
v1.0.0Browse well-known TCP/UDP ports with protocols, services, and security notes.
46 ports found
File Transfer Protocol — data transfer channel.
File Transfer Protocol — command/control channel.
Secure Shell — encrypted remote access and file transfer (SCP/SFTP).
⚠ Change default port in production
Unencrypted remote terminal. Obsolete — use SSH instead.
⚠ Insecure — avoid in production
Simple Mail Transfer Protocol — server-to-server email relay.
⚠ Outbound often blocked by ISPs
Domain Name System — resolves hostnames to IP addresses. TCP for zone transfers.
Dynamic Host Configuration Protocol — server side (IP assignment).
Dynamic Host Configuration Protocol — client side.
HyperText Transfer Protocol — unencrypted web traffic.
Post Office Protocol v3 — retrieves email from server.
Internet Message Access Protocol — synchronises email with server.
Lightweight Directory Access Protocol — directory services and Active Directory.
HTTP over TLS/SSL — encrypted web traffic.
SMTP over TLS — encrypted legacy email submission.
System log messages (UDP). TCP/514 used by some implementations.
STARTTLS email submission — preferred port for client-to-server email.
⚠ Preferred over 465 for submission
LDAP over TLS — secure directory services.
IMAP over TLS — encrypted email synchronisation.
POP3 over TLS — encrypted email retrieval.
OpenVPN — popular open-source VPN protocol.
Microsoft SQL Server — default database port.
Oracle Database — default listener port.
Apache ZooKeeper — distributed coordination service.
Docker daemon API over HTTP. Never expose publicly.
⚠ Security risk — use 2376 with TLS
Docker daemon API over TLS.
Common default for Node.js apps, React (CRA), Grafana.
MySQL and MariaDB relational database.
Remote Desktop Protocol — Windows remote desktop.
⚠ Frequently brute-forced — restrict IP access
Common dev port for various frameworks (Ember, Phoenix, etc.).
Python Flask default. Also used by macOS AirPlay Receiver.
⚠ Conflicts with macOS AirPlay on port 5000
PostgreSQL relational database.
RabbitMQ message broker — AMQP protocol.
Virtual Network Computing — remote desktop (unencrypted by default).
Redis in-memory data store / cache / pub-sub.
Kubernetes API server — primary control plane endpoint.
Common HTTP alternative port. Django's default dev server.
HTTP alternative / proxy. Tomcat, Jenkins, many dev servers.
HTTPS alternative port. Tomcat, Kubernetes dashboard.
Jupyter Notebook and JupyterLab default port.
SonarQube code quality, PHP-FPM fast CGI.
Prometheus metrics server.
Elasticsearch REST API.
Elasticsearch inter-node communication.
RabbitMQ web management UI.
MongoDB NoSQL document database.
WireGuard VPN — modern, fast, secure VPN protocol.