How to Test if a Port Is Forwarded

by Paul Nelson

Port forwarding is a process that opens up a port on your router and maps it to a specific IP address inside your local area network (LAN). Perform port forwarding when you wish to accept connections from incoming clients to a server running inside your network. Primarily peer-to-peer and multi-player games need port forwarding to function correctly. Incorrectly forwarding a port results in failed incoming connections. Testing port forwarding is useful in confirming the correct operation of the configuration.

Download and install the PFPortCheck software (see Resources).

Double-click on the PFPortCheck icon on the desktop.

Type the port number to check into the "Port Number To Check" text box. The port number is the same as the forwarded port number in your router settings.

Select either the TCP or UDP protocol using the radio buttons on the "Protocol" section. Use the same protocol for the forwarded port number in your router settings.

Click the "Check Me" button to start a test on the defined port. The Windows Firewall software may ask for permission for the PFPortCheck program to access the Internet, click "Allow" on the pop-up window to un-block the program.

Identify the results of successful port forwarding by looking at the result given after the "Port Check Result" label.


  • check Ensure that your firewall is not blocking the program whose port you are trying to forward to.

Items you will need

About the Author

Paul Nelson started writing in 2009. He has worked for "The Gaudie," a local campus newspaper, as well as Internet start-ups such as JustNom. Nelson is completing a Bachelor of Science in biomedical sciences at a university in Scotland.