How to make a Minecraft Java server: ports, mods, admins
Updated 2 November 2026 · 7 minute read · Minecraft: Java Edition, your own PC or a rented server · By Exclsv Support
A Minecraft Java server is one file, server.jar from minecraft.net, run with Java on a computer that stays on. Accept the EULA, open TCP port 25565, make yourself an operator with /op, and pick Paper for plugins or Fabric or NeoForge for mods.
What you need
- A Windows, Mac or Linux computer that stays on while people play.
- The Java version your Minecraft version needs. Current versions need a recent 64-bit Java; the Minecraft Wiki lists which version goes with which release.
- Memory: 2 GB suits vanilla with up to 10 friends and 4 GB about 20 players on Paper. Modpacks need more: about 8 GB for Create or RLCraft, 12 GB for All the Mods.
- Access to your router to forward the port.
Install and start it
- Download the server .jar for your version from minecraft.net and put it in an empty folder.
- Start it with java -Xms4G -Xmx4G -jar server.jar nogui (4 GB here; change the numbers to suit).
- The first run stops straight away and makes eula.txt. Read Mojang’s EULA, change the line to eula=true and start it again.
- When the console says Done, join from Minecraft: Multiplayer, Add Server, and your address.
Ports to open
| Port | Protocol | What it’s for |
|---|---|---|
| 25565 | TCP | The game port. Forward it; players add :port to the address only if you change it. |
| 19132 | UDP | Only with Geyser, for Bedrock players on phones and Windows. |
| 25575 | TCP | Remote console (RCON), off by default. Keep it closed to the internet. |
Settings: server.properties
server.properties is made on the first start. The lines most people change:
- motd: the line under the name in the server list.
- difficulty, gamemode and max-players.
- white-list=true and enforce-whitelist=true: only listed players can join.
- view-distance and simulation-distance: lower them first if the server lags.
- online-mode=true: leave it on. Turning it off lets anyone join as any name.
Restart the server after editing it.
Operators and the whitelist
In the server console, type op YourName to make yourself an operator (no slash in the console). Operators can then use commands in game: /whitelist add Name, /kick Name, /ban Name and /gamemode. The lists are kept in ops.json, whitelist.json and banned-players.json.
Plugins, mods and modpacks
- Paper (papermc.io) replaces server.jar and runs plugins from the plugins folder. Players don’t install anything, and it runs more players on the same memory than vanilla.
- Fabric or NeoForge run mods from the mods folder. Every player needs the same mods and loader version.
- Modpacks: download the pack’s server files from CurseForge or Modrinth, not the client pack, and start them as their instructions say.
The easy way: on Exclsv
On an Exclsv server you choose Vanilla, Paper, Fabric, Forge, NeoForge or a CurseForge modpack, and switch later from HQ. The EULA, Java version, memory flags and port are handled for you, and every setting in server.properties is a form with a plain-English line. Memory is reserved for your world, never shared.
| Memory | Suits | Price a month |
|---|---|---|
| 2 GB | Vanilla, up to 10 friends | £4.99 |
| 4 GB | About 20 players, Paper | £8.99 |
| 6 GB | Mods, plugins or a light modpack | £12.99 |
| 8 GB | Create, RLCraft and similar | £16.99 |
| 12 GB | All the Mods and other large packs | £24.99 |
| 16 GB | Large packs, 30+ players | £33.99 |
| 24 GB | Very large worlds, small networks | £49.99 |
| 32 GB | Networks behind a proxy | £69.99 |
Minecraft Java plans and what each includes
If it doesn’t work
“Connection refused” or “Can’t connect to server”
Check the server says Done, TCP 25565 is forwarded to the right computer, and your firewall lets Java through. Friends outside your home use your public address.
“Outdated server” or “Outdated client”
Players need the same Minecraft version as the server. In the launcher, make an installation for the server’s version.
The server crashes with an out of memory error
Raise -Xmx, but leave a couple of GB for the system. If the computer has no more to give, trim mods, lower the view distance or use a bigger machine.
Friends on your own home network can’t join with the public address
Some home routers don’t let devices inside the house reach the house’s own public address. People at home join with the server PC’s local network address instead; everyone else uses the public one.
Run this on Exclsv: Minecraft Java server hosting, from £4.99 a month