How to Play Project Zomboid with Radmin VPN or Hamachi (No Port Forwarding)
Radmin VPN and Hamachi put you and your friends on a private network over the internet, as if you were in the same house, so you don't need to open ports on your router. The host opens the game (with “Host” or a dedicated server) and the others join through “Join” → “Favorites” with the IP the program gives the host and port 16261. Before that, try the Steam invite: it's often enough.
Do you need a VPN?
With “Host”, your friends join through a Steam invite and usually nothing needs opening; if they can't connect, turning on Steam Relay in the connection options usually fixes it (how to host with “Host”).
A VPN is for when that fails, or for a dedicated server at home when you can't open ports 16261 and 16262: your router won't let you, or your ISP uses CG-NAT and nobody can reach you from outside even if you open them (how to tell if you're behind CG-NAT).
Rather not set it up yourself? Project Zomboid servers from €12 a month, no contract and a full refund within 72 hours. Or create a free Project Zomboid server, no card needed.
Radmin VPN or Hamachi
Radmin VPN is free, has no ads and, according to its website, no player limit. It's Windows only. Each PC gets an address starting with 26.
Hamachi is free for up to 5 computers per network (including yours), and has versions for Windows, Mac and Linux. Its addresses start with 25.
For a group of friends on Windows, Radmin VPN is the simplest. Both work the same with Zomboid: the only thing that changes is the IP you type.
Step by step with Radmin VPN
Everyone installs it
The host and each friend, from the official Radmin VPN website. When installing, Windows may ask whether to allow a new network adapter: say yes.
The host creates the network
With the “Create network” button: a name for the network and a password. Send them to your friends privately.
The others join
With the “Join network” button, typing that name and password. Once in, each one shows up in the list with their IP, the one starting with 26.
Open the game
The host starts the game and opens it with “Host” (or starts their dedicated server) and waits until they're in.
Copy the host's IP
In Radmin VPN, the IP shown next to the host PC's name, for example 26.12.34.56. That's the server address, not the host's home IP.
Join through “Join”
Each friend, in the game: “Join” → “Favorites”, adds a server with that IP and port 16261, enters their username and a password for their account, saves and joins. The first time, their account on that server is created.
With Hamachi, the same
The host creates the network (“Create a new network”), with an ID and a password; the others join with “Join an existing network”. The address you type in the game is the host's Hamachi IPv4, the one starting with 25, with port 16261. If there are more than 5 of you, the free version won't do: use Radmin VPN.
If it won't connect over the VPN
The host's Windows firewall comes first: the VPN network is usually set as a public network, and if you said no to “Allow access” when opening the game or the server, it blocks your friends. Create an inbound UDP rule for ports 16261 and 16262 that also applies on public networks (how to do it).
Check that you're all on the same game version and the same Steam branch, and that the host has the game open: if they quit, it ends for everyone. If a mod doesn't download or doesn't match, it kicks you out while loading: the usual causes.
If it stutters, check the connection status in the program: when it can't link two PCs directly, traffic takes a detour through its servers and ping goes up.
The downsides of playing over a VPN
You all have to install the program and keep it open to play, and anyone who joins your Radmin or Hamachi network is, network-wise, inside your house: create the network only for friends you trust, and with a password.
And it's still your PC acting as the server: if you close it, nobody plays, and with Build 42 the server takes a good chunk of the RAM. When the game is going to last weeks or you want to play without the host, a server outside your home makes more sense (the three ways to play with friends).
With NapNodes, no VPN
A rented server is already on the internet: everyone joins through “Join” → “Favorites” with the address and port shown on the panel's “Address to play” card, without installing anything or opening ports, and the game carries on even when you're not there. To try it without paying, the free Project Zomboid server, with 6 GB and no card, which you start when you want to play.
Frequently asked questions
Can you play Project Zomboid with Radmin VPN?
Yes. The host creates a network in Radmin VPN, the others join it and connect through “Join” → “Favorites” with the host's Radmin IP (the one starting with 26) and port 16261.
What IP do I use in Project Zomboid with Hamachi?
The Hamachi IPv4 of whoever hosts the game, the one starting with 25, with port 16261. Not their home IP.
Do I need to port forward if I use Radmin VPN?
No: the VPN puts you on the same network. What you do need is to let the game through the host's Windows firewall, on public networks too.
How many friends can join over Hamachi?
With the free version, 5 computers per network including yours. Radmin VPN doesn't have that limit.
Can my friends play over the VPN when I'm not on?
No: the game lives on your PC and closes when you quit. For them to play without you, you need a server that's always on.
Shall we set it up for you?
Project Zomboid servers from €12 a month, never oversold: your RAM is yours alone. And if you'd rather start without paying, there's a free Project Zomboid server, no card needed.
Not sure whether your server is online? Check it in a second with the Project Zomboid server status checker: players, version and password, free.