How to Forward Ports on Your Router

Some games and programs only work if you open a specific port

Specific ports must be open on your router for some video games and programs to work properly. Although the router has some ports open by default, most are closed and only usable if you manually open these ports. When your online video games, file server, or other networking programs don't work, access the router and open the specific ports that the application needs.

Person port forwarding on their router
Maddy Price / Lifewire

How Do You Set Up Port Forwarding?

The traffic that passes through your router does so through ports. Every port is like a special pipe made for a specific kind of traffic. When you open a port on a router, it allows a particular data type to move through the router.

The act of opening a port, and choosing a device on the network to forward those requests to, is called port forwarding. Port forwarding is like attaching a pipe from the router to the device that needs to use the port—there's a direct line-of-sight between the two that allows data flow.

For example, FTP servers listen for incoming connections on port 21. If you have an FTP server set up that nobody outside your network can connect to, open port 21 on the router and forward it to the computer you use as the server. When you do this, that new, dedicated pipe moves files from the server, through the router, and out of the network to the FTP client that's communicating with it.

Port 21 open on a router

The same is true for other scenarios like video games that need the internet to communicate with other players, torrent clients that require specific ports to be open for uploading files, and instant messaging applications that only send and receive messages through a specific port.

Every networking application needs a port to run on, so if a program or application isn't working when everything else is set up correctly, open the port on the router and forward requests to the right device (for example, a computer, printer, or game console).

Port range forwarding is similar to port forwarding but is used to forward an entire range of ports. A certain video game might use ports 3478 through 3480, for example, so instead of typing all three into the router as separate port forwards, forward that whole range to the computer running that game.

Below are two primary steps you need to complete to forward ports on a router. Because every device is different, and because there are many router variations, these steps are not specific to any device. If you need additional help, refer to the user manual for the device, for example, the user guide for your router.

Give the Device a Static IP Address

The device that will benefit from the port forward needs to have a static IP address. This way, you don't have to change the port forwarding settings each time it obtains a new IP address.

For example, if your computer runs torrenting software, assign a static IP address to that computer. If your gaming console uses a specific range of ports, it needs a static IP address.

There are two ways to do this: from the router and from the computer. When you set up a static IP address for your computer, it's easier to do it there.

Use Your Computer to Set Up a Static IP Address

To set up a Windows computer to use a static IP address, first identify which IP address it's using currently.

  1. Open Command Prompt on the computer.

    Screenshot of Command Prompt window
  2. Type this command, then press Enter:

    
    
    A screenshot of Command Prompt with the ipconfig /all command highlighted
  3. Record the following: IPv4 Address, Subnet Mask, Default Gateway, and DNS Servers.

    A screenshot of Command Prompt with elements highlighted

If you see more than one IPv4 Address entry, look for the one under a heading like Ethernet adapter Local Area Connection, Ethernet adapter Ethernet, or Ethernet LAN adapter Wi-Fi. Ignore anything else, like Bluetooth, VMware, VirtualBox, and other non-default entries.

Now, you can use that information to set up the static IP address.

  1. Open the Run dialog box (press WIN+R), enter ncpa.cpl, and select OK to open Network Connections.

    Screenshot of Run dialog with ncpa.cpl command
  2. Right-click or tap-and-hold the connection that has the same name as the one you identified in Command Prompt. For example, Ethernet0.

  3. Select Properties from the menu.

    A screenshot of the Windows Network Connection window with the Properties command highlighted
  4. Choose Internet Protocol Version 4 (TCP/IPv4) from the list, then select Properties.

    Network Connection settings in Windows with IPV4 and Properties highlighted
  5. Select Use the following IP address.

    Windows Network Connection window with the "Use the following IP address" item highlighted
  6. Enter the details you copied from Command Prompt: IP address, subnet mask, default gateway, and DNS servers.

    Network Connections in Windows with manual IP address fields highlighted
  7. Choose OK when you're done.

    Network Connections window in Windows with the OK button highlighted

If you have several devices on your network that get IP addresses from DHCP, don't reserve the same IP address you found in Command Prompt. For example, if DHCP is set up to serve addresses from a pool between 192.168.1.2 and 192.168.1.20, configure the IP address to use a static IP address that falls outside that range to avoid address conflicts. For example, use 192.168.1.21 or above. If you're not sure what this means, add 10 or 20 to the last digit in your IP address and use that as the static IP in Windows.

You can also set up a Mac to use a static IP address, as well as Ubuntu and other Linux distributions.

Use Your Router to Set Up a Static IP Address

Another option is to use the router to set up a static IP address. Do this when a non-computer device needs an unchanging address (like a gaming console or a printer).

  1. Access the router as admin.

    Screenshot of router login
  2. Locate a Client List, DHCP Pool, DHCP Reservation, or similar section of the settings. The section lists the devices currently connected to the router. The IP address of the device is listed along with its name.

    Screenshot of DHCP Settings
  3. Look for a way to reserve one of those IP addresses to tie it with that device so that the router always uses it when the device requests an IP address. You might need to select the IP address from a list or choose Add or Reserve.

The above steps are generic since static IP address assignment is different for each router, printer, and gaming device. Follow these links for instructions on reserving IP addresses for NETGEARGoogleLinksysXbox OnePlayStation 4, and Canon printers..

To make your public IP address static so that you can access your devices from an outside network, pay for a static IP. A workaround involving setting up a dynamic DNS service is just as helpful.

Set Up Port Forwarding

Now that you know the device's IP address and configured it to stop changing, access the router and set up the port forwarding settings.

  1. Log in to the router as admin. You need to know the router's IP address, username, and password.

    Screenshot of router login
  2. Locate the port forwarding options. These are different for every router but might be called something like Port Forwarding, Port Triggering, Applications & Gaming, or Port Range Forwarding. These might be buried within other categories of settings like Network, Wireless, or Advanced.

    A screenshot of TP-Link with the Forwarding option highlighted
  3. Type the port number or port range that you want to forward. If you're forwarding one port, type the same number under both the Internal and External boxes. For port ranges, use the Start and End boxes.

    Most games and programs indicate which ports must be open on the router. If you don't know what numbers to type here, PortForward.com has a list of common ports.

    Screenshot of port forwarding
  4. Choose a protocol, either TCP or UDP. Choose both, if needed. This information should be available from the program or game that explains the port number.

    Screenshot of TCP and UDP protocols
  5. Type the static IP address you chose.

    If asked, name the port trigger anything that makes sense to you. If it's for an FTP program, call it FTP. Call it Medal of Honor if you need the port open for that game.

    Screenshot of static IP
  6. Enable the port forwarding rule with an Enable or On option. 

Here's an example of what it looks like to forward ports on a Linksys WRT610N:

Port forwarding settings on a Linksys WRT610N

Some routers have a port forward setup wizard that makes it easier to configure. For example, the router might first give you a list of devices already using a static IP address and then let you choose the protocol and port number from there.

Here are some other port forwarding instructions that are more specific to these brands of routers: D-Link, NETGEAR, TP-Link, Belkin, Google, Linksys.

More on Open Ports

If forwarding a port on your router doesn't allow the program or game to work on your computer, find out if a firewall program blocked the port. The same port needs to be open on the router and your computer for the application to use it.

Port 21 open in the Windows 10 firewall

To see if the Windows Firewall is blocking a port that you opened on the router, temporarily disable the firewall and then test the port again. If the port is closed on the firewall, edit some settings to open it.

When you open a port on the router, traffic can flow in and out of it. When you scan the network for open ports, you should see everything that's open from the outside. There are websites and tools build specifically for this.

Here are some reasons why you would check for open ports:

  • To avoid getting into the router to check.
  • To make sure the port opened correctly when a program or game isn't working.
  • To make sure a port you closed is actually closed.
NetworkAppers open port check tool

Several places offer a free open port checker. PortChecker.co and NetworkAppers have online port checkers that scan a network from the outside. Advanced Port Scanner and FreePortScanner are useful for scanning other devices within your private network.

Only one port forward can exist for every instance of that port. For example, if you forward port 3389 (used by the Remote Desktop remote access program) to a computer with the IP address 192.168.1.115, that same router can't also forward port 3389 to 192.168.1.120.

In cases like this, the only solution, if possible, is to change the port the program uses. This may be possible from the software settings or through a registry hack. In the RDP example, if you edit the Windows Registry on the 192.168.1.120 computer to force Remote Desktop to use a different port like 3390, you could set up a new port forward for that port and use Remote Desktop on two computers within the same network.