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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.

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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  1. 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 --installServer
  2. Fabric: 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.

  3. 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.

Which of the three a mod is decides whether it belongs in the server's mods folder at all.
Kind of modGoes on the serverWhat it does
Server-sideYesWorld generation, new blocks, recipes, mechanics. The server has to compute all of it.
Both sidesYes, same versionMost content mods. Server and client have to agree, down to the version number.
Client-onlyNoRendering 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.

The six packs this site hosts, each with the number from its own page.
ModpackMemory it asks forSmallest plan that covers it
RLCraftForge6 - 8 GBA block of coal, the icon of the Starter Minecraft server planStarter, 8 GB
All The Mods 10NeoForge8 - 12 GBA block of iron, the icon of the Standard Minecraft server planStandard, 12 GB
PixelmonForge4 - 6 GBA block of coal, the icon of the Starter Minecraft server planStarter, 8 GB
CreateForge or Fabric4 - 6 GBA block of coal, the icon of the Starter Minecraft server planStarter, 8 GB
SevTech: Ages6 - 8 GBA block of coal, the icon of the Starter Minecraft server planStarter, 8 GB
Vault Hunters8 GB+A block of coal, the icon of the Starter Minecraft server planStarter, 8 GB

Per pack: RLCraft, All The Mods 10, Pixelmon, Create.

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

See 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.