How to add mods to your Minecraft server

Mods or plugins?

Plugins (Paper, Spigot, Purpur) run only on the server; players join with plain Minecraft. Mods need a mod loader on the server and usually the same mods on each player's game. If what you want exists as a plugin (economy, claims, homes, permissions), a plugin server is simpler. For new blocks, mobs and dimensions you need mods.

1. Pick a mod loader

• Fabric: light and quick to update to new Minecraft versions. Great for performance mods and smaller content mods.
• NeoForge: the modern home of big content mods on recent versions.
• Forge: most older modpacks (1.12, 1.16, 1.18, 1.20.1) are Forge.
• Quilt: a Fabric fork that runs most Fabric mods.

A mod's download page says which loader and Minecraft versions it supports. Pick the loader that most of your mods share; you can't mix Fabric and Forge mods on one server.

2. Set the server to that loader

On Jump, pick the loader when you create a server, or switch later in Settings → Software & version. Switching between loaders usually means a fresh world, since modded worlds don't carry across; the panel tells you and backs up first on paid plans.

3. Install the mods

1. Open Plugins & mods in the panel and search. The catalog comes from Modrinth and only shows mods that fit your loader and version.
2. Click Install for each mod, and install the libraries it needs too (Fabric mods usually need Fabric API).
3. For a mod that isn't in the catalog, upload its .jar into the mods folder in Files (or over SFTP).
4. Restart the server. Its console shows each mod loading.

Mods marked client-only (Sodium, Iris, minimaps, shaders) belong on players' games, not the server. Jump labels them and won't install them on a server.

4. Set up players' games

Each player needs the same loader, Minecraft version and content mods. The easy way is a launcher such as the Modrinth App, CurseForge or Prism Launcher: make an instance with the loader and add the same mods. Server-side-only mods (Lithium, FerriteCore, Chunky) aren't needed on clients.

When it crashes

• "Mismatched mod list" or "incompatible mods" on join: the player's mods or versions differ from the server's. Compare the two lists.
• Crash on start naming a missing dependency: install the mod it names (often an API or library mod).
• Out of memory: big mod lists need more than 2 GB. Remove a few heavy mods or move to a bigger plan.
• A client-only mod on the server: remove it from mods/.

The troubleshooting guide covers reading the console and crash reports.

Questions