Guide
8 min readJun 21, 2026

How to Check and Change NAT Type on PC and Windows 11

A complete PC NAT type change guide: test your NAT type first, try UPnP or DMZ, fix CGNAT or Double NAT, then choose a VPN workaround or FRP tunneling when normal fixes are blocked.

Quick Answer

Do not start by changing random Windows settings. NAT type is usually decided by your router and upstream network path. Follow this order:

1

Test NAT type first

Test your NAT type with NATChecker.com first. If the result is Full Cone, there is usually nothing to fix. Continue only for Restricted Cone, Port Restricted Cone, or Symmetric NAT.

2

Enable UPnP or DMZ on the router

UPnP is the first option. If it does not work, DMZ can be used for a dedicated PC after assigning that PC a stable LAN IP.

3

Check CGNAT or Double NAT

If router settings do not change the NAT result, the blocking point is often outside the Windows PC itself.

4

Retest after each change

Change one layer at a time, then run the NAT test again so you know which step actually changed the result.

5

Use VPN or FRP if normal fixes are not possible

VPN is the easier workaround for most players, while FRP can expose selected ports through a public server. Neither option changes the whole network NAT type.

I put this guide together after testing NAT changes on my own Windows PC and home router. My hands-on testing was done in my country, so router pages and ISP policies may look different elsewhere. But the problems people describe in gaming and networking communities are usually the same: the NAT result does not change after router settings, the line is behind CGNAT, or two routers are creating Double NAT. That is why the method below focuses on the network path instead of random Windows tweaks.

How to Check NAT type on PC / Windows 11?

Use NATChecker.com on the same Windows PC and the same network where the connection problem happens. NATChecker.com is a free NAT type checker used by more than 2,000 people every day and ranked #1 on Google for NAT checker searches. Although the tool was freshly released in July 2025, it quickly outranked many older alternatives because the test is fast, accurate, and free.

NAT resultWhat it meansWhat to do next
Full Cone NATThe best result for direct peer connections and hosting behavior.Stop here unless a specific game or app still has its own connection issue.
Restricted Cone NATUsually usable, but inbound peer behavior can still be limited.Continue with UPnP or DMZ if you need better P2P, hosting, or matchmaking behavior.
Port Restricted Cone NATMore restrictive because the remote address and port both matter.Continue with router-side changes and upstream NAT checks.
Symmetric NATThe most restrictive result and a common cause of failed P2P connections.Continue through every step in this guide, especially CGNAT and Double NAT checks.

The goal is not to change settings blindly. The goal is to know whether your PC already has a high-grade NAT result or whether the network path needs to be changed.

How to Change NAT type on PC / Windows 11?

Step 1Enable UPnP or DMZ on Your Router

If your NAT type is not Full Cone, the first useful fix is usually on the router. Try UPnP first. If UPnP does not change the result, DMZ can be used as the next router-side test.

Option A: Enable UPnP

UPnP lets apps and games ask the router to create temporary mappings automatically.

  1. 1. Open your router admin page.
  2. 2. Find UPnP under NAT, Advanced, Internet, or Gaming settings.
  3. 3. Enable UPnP, save the setting, then restart the game or reconnect the PC.
  4. 4. Run the NAT test again and compare the result.

Option B: Try DMZ for the PC

DMZ forwards unsolicited inbound traffic to one LAN device. Use it only for the Windows PC you are testing.

  1. 1. Reserve a stable LAN IP for the Windows PC in the router.
  2. 2. Find the router's DMZ setting.
  3. 3. Set the Windows PC LAN IP as the DMZ host and save.
  4. 4. Retest NAT type from the same PC.

DMZ is useful for diagnosis, but it exposes more traffic to the selected PC than UPnP does. Use it only for the PC you are testing.

Port forwarding is worth using only when UPnP or DMZ can work on this network and you only want to expose specific ports. If both UPnP and DMZ do not change the NAT result, port forwarding is usually a waste of time, so do not keep tuning that option.

Step 2If NAT Does Not Change, Check CGNAT or Double NAT

If UPnP or DMZ does not change the NAT result, the router may not be the final device controlling inbound traffic. Check the upstream path.

Check for CGNAT

CGNAT means the ISP is sharing one public IPv4 address across many customers. If your line is behind CGNAT, local router settings cannot create direct inbound reachability. Contact the ISP and ask for a public IPv4 address or a static public IP option.

Open the CGNAT checker guide

Check for Double NAT

Double NAT happens when two devices are both routing, such as an ISP gateway plus your own router, a mesh router behind another router, or chained home routers. Reduce the network topology: use bridge mode, AP mode, or keep only one main NAT router.

Open the Double NAT guide

Step 3Retest NAT Type After Each Change

Retest after every major change. This keeps the process clear and prevents you from changing multiple layers without knowing which one mattered.

  1. 1. Test the original NAT type.
  2. 2. Enable UPnP, then test again.
  3. 3. Try DMZ for the Windows PC, then test again.
  4. 4. Fix CGNAT or Double NAT if found, then test again.
Run the NAT test

Step 4Use a VPN or FRP Workaround

If router settings, CGNAT changes, or topology changes are not possible, choose a workaround based on the job. Try a VPN first when you want the simplest app-based test for games or peer connections. Use FRP when you know the exact TCP or UDP port and can route it through a public server.

Important distinction

VPN and FRP usually do not change the NAT type of your home router. They can still make the affected game, room, server, or service reachable in ways that feel like a better NAT result. A normal NAT checker may still show the same NAT result.

Option A: VPN for the easiest test

Best for regular players who do not want to manage a server. Install the VPN app, connect to a suitable region, enable port forwarding if the provider requires it, then retest the affected game or service.

Option B: FRP for known ports

Best for technical users hosting a game server, web service, or another app with documented ports. You run frps on a public server, frpc on the Windows PC, and map only the ports you need.

Choose a VPN that supports port forwarding

Not every VPN can help with NAT-style reachability. Prefer a provider with documented port forwarding and a flexible refund policy, so you can test whether it fixes your specific game or service before keeping it.

Public server options for FRP

FRP needs a server with a public IP address. Pick a region close to the players or clients who will connect to you. Lower latency matters more than raw CPU for most game and app ports.

I have not published a dedicated FRP setup guide yet. For now, you can ask an AI assistant for an FRP configuration example based on your exact server, port, and protocol. If you want me to write a step-by-step FRP tutorial for NATChecker, send me a note at admin@natchecker.com. If enough readers ask for it, I will turn it into a separate guide.

Hosting a game server

Expose only the server port that outside players need to reach.

Publishing a service port

Forward one controlled TCP or UDP port instead of opening the whole PC.

Working around CGNAT

Use a public server as the reachable endpoint when the ISP cannot provide public IPv4.

FAQ

How do I get Open NAT type on PC?

To get Open NAT behavior on a PC, first confirm your current NAT type, then enable UPnP on the router. If UPnP does not work, try DMZ for the Windows PC after assigning it a stable LAN IP. If the result still does not change, the real blocker is usually CGNAT, Double NAT, or an upstream router you do not control.

Why is my NAT type strict on PC?

Strict NAT on PC usually means inbound peer connections cannot reach your device cleanly. Common causes include disabled UPnP, no working DMZ or port mapping, CGNAT from the ISP, Double NAT at home, or Symmetric NAT behavior upstream.

Read the full strict NAT guide

What does Port Restricted NAT mean?

Port Restricted NAT means the router allows return traffic only from the specific remote IP address and remote port your PC contacted first. It is usually more restrictive than Restricted Cone NAT and can cause problems for P2P games, voice chat, hosting, and direct multiplayer sessions.

Why is my NAT still strict after enabling UPnP or DMZ?

If UPnP or DMZ does not change the NAT result, your router may not be the final NAT device. Check whether your ISP is using CGNAT, or whether your home network has Double NAT from an ISP gateway, mesh router, or chained routers.

Run the NAT Test

Start by checking your current NAT type from this Windows PC. If it is already Full Cone, you usually do not need the rest of the guide.

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