The port number lookup tool searches the IANA port registry — over 500 well-known and registered ports with protocol, service name, description, and security notes. Search by port number or service name to instantly identify any TCP/UDP port.
Quick Access
| Port | Protocol | Service | Description | Category | Copy |
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How to Use the Port Number Lookup Tool
The port number lookup tool contains the complete IANA registry of well-known (0-1023) and commonly registered (1024-49151) ports. All data is embedded locally — no internet connection required after the page loads, and searches are instant.
Search Options
- By number: enter any port number 0-65535
- By service name: type "ssh", "http", "mysql", "redis", etc.
- By keyword: search descriptions — try "database", "email", "gaming"
- Autocomplete: suggestions appear as you type — click to select
Filter Options
- Well-Known (0-1023) — IANA-assigned system services, require root/admin to bind
- Registered (1024-49151) — Application ports registered with IANA, user-space bindable
- TCP Only / UDP Only — filter by transport protocol
Quick Access Categories
Click the category buttons (Web, Database, Email, Remote Access) to instantly view all ports in that category. Useful for firewall configuration and network security reviews.
Security Notes
Click any row to expand security details — including whether the service is encrypted, common attack vectors, and recommended alternatives. Ports 23 (Telnet), 21 (FTP), and 110 (POP3) transmit credentials in plaintext and should be avoided in production.
Firewall Configuration Reference
Use the copy button to copy port information for firewall rules documentation. For a web server, you'd typically open ports 80 and 443. For email, open 587 (SMTP submission) and 993 (IMAPS) for modern mail clients — avoid opening 25 inbound unless you're running your own mail server.
FAQ
What is a port number?
A port number is a 16-bit number (0-65535) that identifies a specific process or network service on a computer. When you connect to a web server, your browser connects to port 80 (HTTP) or 443 (HTTPS). Port numbers allow multiple services to run on the same IP address. The OS uses ports to route incoming network packets to the right application.
What are well-known ports vs registered ports?
Well-known ports (0-1023) are assigned by IANA for major protocols and require administrator privileges to use. Examples: 80 (HTTP), 443 (HTTPS), 22 (SSH), 25 (SMTP). Registered ports (1024-49151) are registered with IANA for specific services but don't require root access. Dynamic/private ports (49152-65535) are used for temporary connections.
What is the difference between TCP and UDP ports?
TCP (Transmission Control Protocol) provides reliable, ordered, connection-based communication with error checking. It's used for web browsing, email, SSH, and file transfers. UDP (User Datagram Protocol) is faster but connectionless and unreliable — suitable for streaming, DNS, gaming, and VoIP where speed matters more than guaranteed delivery. Some services (like DNS on port 53) use both protocols.
How do I check which ports are open on my computer?
On Windows, run 'netstat -an' or 'Get-NetTCPConnection' in PowerShell. On Linux/Mac, use 'ss -tlnp' or 'netstat -tlnp' to see listening TCP ports. The port lookup tool shows which service is expected on a port, but for actual open ports on your system you need to run these local commands.
Is this port lookup tool free?
Yes, completely free. The entire port registry is embedded in the tool — no external API calls are needed. All searches happen locally in your browser with no data sent to any server.
Is my search data private?
Yes. The port database is embedded in the tool JavaScript. All searches happen in your browser with no network requests. Your search terms never leave your device.