How to Install Modpacks on Your Minecraft Server
Modpacks bundle dozens or hundreds of mods into a single download. Getting one running on a server is two decisions and then a folder of files in the right place.
The short answer
The pack decides the loader
Forge or Fabric, whichever the pack was built for. The server runs that one and nothing else.
Server pack first, by hand second
If the pack offers a server pack, upload that. Otherwise copy the mods folder and take out the client-side ones.
Same mods, same versions, everyone
A player with one mod more or one version off sees missing textures or cannot join at all.
Both methods, the client-side list and the memory table below are those three lines in detail.
Forge vs. Fabric: Which Loader Do You Need?
Before you install anything you need to know which mod loader your pack uses. Forge has been around since 2011 and carries most of the big packs; NeoForge is the fork that newer Forge packs moved to. Fabric is lighter and updates to new Minecraft versions much faster. The pack's own page on CurseForge or Modrinth says which one it needs, and so does every pack page on this site. The two are not interchangeable: you cannot mix Forge mods with Fabric mods, and a Forge pack will not start on a Fabric server. Pick the loader your pack names and stay on it.
Method 1: Server Pack Download (Easiest)
Most packs on CurseForge and Modrinth ship a separate server pack: one zip with the loader, the server-side mods and the default configs already in it. If your pack has one, use it. Nothing else on this page is as hard to get wrong.
Download the server pack
On the pack page, open the version you want and look for a file called Server Pack or Server Files. Unzip it on your own machine first. You should see a loader jar, a mods folder and a config folder sitting next to each other.
Empty the server first
Open the file manager in the panel and move or delete what is left of any earlier setup. Mods from a previous pack that stay behind are the single most common reason a server pack will not boot.
Upload into the root, not into a subfolder
The jar, the mods folder and the config folder belong in the server root. If the zip unpacked into a folder of its own, upload what is inside that folder and not the folder itself.
Point the startup at the loader jar
In the startup tab, set the server jar to the file the pack shipped, and set the memory to what the pack asks for. The table further down has that number for every pack we host.
Start it and wait longer than feels right
A heavy pack takes three to five minutes on its first boot: the loader has to build its registry before the world exists. It only does that once. If the console has gone quiet rather than scrolling, that is when to go looking for a crash.
Method 2: Manual Mod Installation
No server pack, or your own hand-picked collection of mods: then you build the server first and add the mods afterwards.
Forge: run the installer with --installServer
Download the installer for your exact Minecraft version from the official Forge site, run it on your own machine with the server flag, and upload everything it produced.
java -jar forge-installer.jar --installServerFabric: upload the launcher and let it fetch the rest
Download the Fabric server launcher from fabricmc.net, upload it to the server root and set it as the startup jar. On the first run it downloads what it needs by itself.
Create the mods folder and fill it
If there is no mods folder yet, make one in the server root, then upload the mod jars into it. Add two or three at a time and restart in between. Twenty at once tells you nothing about which one broke it.
Client-Side vs. Server-Side Mods
Not every mod in a pack belongs on the server. The mod's page on CurseForge or Modrinth says which side it is for, and the server pack from method one has already made that choice for you.
| Kind of mod | Goes on the server | What it does |
|---|---|---|
| Server-side | Yes | World generation, new blocks, recipes, mechanics. The server has to compute all of it. |
| Both sides | Yes, same version | Most content mods. Server and client have to agree, down to the version number. |
| Client-only | No | Rendering and interface: Optifine, Sodium, Iris, minimaps and HUD mods. Usually ignored on a server, occasionally a crash. |
Keeping Mods in Sync
The server and every client have to run the same version of every shared mod. Version 1.5.2 on the server against 1.5.3 on a player's machine is a rejected connection with a mod mismatch, not a warning. The way out is to make the launcher do it: CurseForge, Prism Launcher and the Modrinth App all import a pack by code or URL, so when you move the server to a new pack version you tell people which version to switch to and the launcher fetches it.
RAM and Performance Considerations
A modded server is a different machine from a vanilla one: the loader keeps every mod's registry in memory whether anyone is near it or not. Rather than repeat the general table, here are the six packs we actually host, with the number from their own page and the smallest plan that clears it. 0 of the 6 fit in Mini. The general rows by mod count, and what they assume, are in our memory guide.
| Modpack | Memory it asks for | Smallest plan that covers it |
|---|---|---|
| RLCraftForge | 6 - 8 GB |  Starter, 8 GB |
| All The Mods 10NeoForge | 8 - 12 GB |  Standard, 12 GB |
| PixelmonForge | 4 - 6 GB | Starter, 8 GB |
| CreateForge or Fabric | 4 - 6 GB | Starter, 8 GB |
| SevTech: Ages | 6 - 8 GB | Starter, 8 GB |
| Vault Hunters | 8 GB+ | Starter, 8 GB |
Per pack: RLCraft, All The Mods 10, Pixelmon, Create.
What the AI does and does not do here
Worth being exact about, because a modpack is the one case where the AI Copilot does not do the install: it installs from a vetted list of plugins for the Paper family, and a Forge or Fabric server runs a different loader, so it refuses rather than dropping a jar that cannot load anyway. What it does do on a modded server is read: your crash report, your startup log, the memory the container is really using and the files in your pack folder, and then it tells you which mod fell over first and what it wants. The AI performance optimizer reads the same server for tick time, tick rate, memory and garbage collection; the census of entities per type in it is a Paper command, so on Forge and Fabric you get the rest of the pass without that one table. Backups it does handle on any server, whatever loader is running: ask for one before you update a pack, and if the update goes wrong, restoring a backup puts your mods, your configs and your world back on the version that worked in one go.
Questions people ask while installing
Can I run plugins on a modded server?
Not directly. Forge, NeoForge and Fabric do not carry the Bukkit API, so a plugin jar does nothing in a mods folder. Hybrid software exists but breaks often. If you need both, run the plugin side on a separate server behind a proxy.
Why does the first startup take so long?
The loader has to walk every mod, resolve what depends on what, and build a registry of blocks and items before a world can exist. Three to five minutes is normal for a heavy pack, and only on the first boot.
The server crashes on boot. Where do I look?
The last few lines before the stack trace in the console, not the trace itself. Nine times out of ten it names a mod, a missing dependency, or a Java version that does not match the loader.
How much RAM should I give a modpack?
What the pack's own page says, and never all of what the plan has: the JVM needs headroom on top of the heap. The table above gives the number for the six packs we host.
Can I swap a pack out for another one later?
Yes, and the plan can move with it, but the world does not: a world built with one pack's blocks loses them when those mods leave. Start a new world when you change packs.
Plans that run these packs
Starter8 GBfrom €11.20 a month on a twenty-four month termStandard12 GBfrom €14.70 a month on a twenty-four month termSee all 21 plans across three editionsAnswer four questions and get the size
The memory next to each pack is the number from that pack's own page on this site, and the plan next to it is the smallest one on our price list that clears it. Both are read when this page is built, so the two pages cannot drift apart.
Why a big pack asks for a faster core
A pack with two hundred mods runs all of them inside the same fifty milliseconds, one after another, on a single core. Memory keeps the pack loaded; core speed decides whether it finishes in time. That is why the packs people call heavy are the clearest case for a plan on an AMD Ryzen 9 5900X.
Written and checked by the Astroworld Hosting team. Last reviewed on 6 September 2026.
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