Common Ports Reference
Find any network port by number or service name. Covers well-known ports (0–1023), registered ports, and common application ports.
Why use a Port Reference?
Port numbers are the language of network services — from SSH on port 22 to HTTPS on 443 to PostgreSQL on 5432. Whether you're writing firewall rules, debugging connectivity, or setting up a new service, you need to know which ports are in use. This reference covers 40+ well-known ports with service names, protocols, and descriptions — searchable and filterable. Combine with DNS lookup and subnet calculator in the networking tools category.
Instant search
Search by port number, service name, or keyword — results filter in real time as you type.
TCP/UDP filter
Filter by protocol to see only TCP or only UDP ports — useful when writing firewall rules that specify protocol.
Security context
Descriptions include security notes — like which ports are high-risk or should be blocked on public-facing interfaces.
Top 10 ports every sysadmin should know
These are the most commonly encountered ports in server administration, security auditing, and network troubleshooting.
| Port | Service | Why it matters |
|---|---|---|
| 22 / TCP | SSH | Primary remote access vector — restrict to trusted IPs, disable password auth |
| 25 / TCP | SMTP | Email delivery — block outbound 25 on non-mail servers to prevent spam abuse |
| 53 / TCP+UDP | DNS | Name resolution — a blocked DNS port breaks almost everything |
| 80 / TCP | HTTP | Plain web traffic — should redirect to HTTPS; never serve sensitive data over HTTP |
| 443 / TCP | HTTPS | Encrypted web traffic — the only port that should serve your web app publicly |
| 3306 / TCP | MySQL | Block from public internet — bind to 127.0.0.1 or use a private subnet |
| 3389 / TCP | RDP | Windows Remote Desktop — one of the most attacked ports on the internet |
| 5432 / TCP | PostgreSQL | Database — never expose to public internet; use SSH tunnels or private VPC |
| 6379 / TCP | Redis | Cache/message broker — unauthenticated by default; always firewall this port |
| 8080 / TCP | HTTP Alt | Dev servers and proxies — typically should not be publicly accessible in production |