How to install mods on Forge, Fabric and NeoForge

Mods change the game itself: new blocks, mobs, machines and worlds. A mod server runs a mod loader, which is one of Fabric, Forge, NeoForge or Quilt. Each mod is built for one loader and one Minecraft version, and every player who joins needs the same mods on their own computer. If you want server-only extras such as homes or ranks, use plugins instead. See How to install plugins on Paper, Spigot and Purpur.

Mods can stop a server from starting, and some of them change the world in ways you cannot undo. Back up before you add one. See How to back up, restore and reset your Minecraft world.

Match the loader and the version first

Mods do not work across loaders. A Fabric mod does not load on Forge, and the other way round. Forge and NeoForge share a history but have split, so a mod for one does not load on the other on current versions. The Quilt loader is made to run Fabric mods, so a Fabric mod is accepted on Quilt.

To see what your server runs, open Overview, where the identity card shows its server type and version. The Mods tab also has a filter called Runs on with your loader's name. To switch loader or version, use Edit Server Type, which deletes the server's files by default. See How to change your Minecraft version or server type. Most mods are published for a handful of Minecraft versions, so pick the version your favourite mods support before you pick anything else.

Install a mod from the Modding tab

The tab searches Modrinth and CurseForge together and puts each file in the mods folder for you.

1. Open your server in the panel and click Modding, then the Mods tab. If there is no Mods tab, your server type does not run mods. Paper, Purpur, Spigot and Folia run plugins, and Vanilla runs neither plugins nor mods. The tab says so and tells you which types to change to. A Vanilla server still shows the Modpacks, Worlds and Datapacks tabs.
2. Type the mod's name in Search mods and press Enter. Source can be All sources, Modrinth or CurseForge. Minecraft version starts on your server's own version.
3. Click Install on the row you want. The panel installs the newest build for the version shown in the Minecraft version filter, which starts on your server's version. To get an older build, change that filter, or download the jar yourself and upload it, as described below. Only pick a version your server can load.
4. If the mod needs libraries, such as Fabric API, a window opens that lists them, and its button reads Install 2 files or similar. Click it to install them together.
5. Restart the server so it loads the mod. The panel does not restart it for you after a single install.

The panel checks a few things before it installs, and it stops with a message instead of leaving you with a server that cannot start:

• A mod built for another loader shows Won't run here on its row.
• A required library that has no build for your version stops the install.
• A mod that needs a newer Java than your server runs stops the install, and the message says which Java it needs. Follow the message, or change the Minecraft version filter to find an older build, or upload an older jar by hand.

A mod whose listing does not name your version simply installs, with no warning, and it may still work. Watch the Console after the restart.

Install a mod by uploading the file

Use this for a mod you downloaded yourself.

1. Download the .jar file from the mod's official page, for the right loader and the right Minecraft version. Download any library it asks for too, such as Fabric API.
2. Open Files, then the mods folder. If it is not there, start the server once and stop it.
3. Click Upload and choose the files. For many files use SFTP. See How to connect to your server files with SFTP.
4. Restart the server.

For a whole pack of mods, a modpack is easier. See How to install a modpack on your Minecraft server.

Check that the mods loaded

1. Open the Console tab and watch the start. A mod that loaded shows in the output, and the Errors filter shows what failed. The first error usually names the mod and what it needs. See How to use the console and run commands.
2. Join the server with the matching mods and look for the new blocks or items.

If the server stops during the start, remove the newest mod, or restore your backup, and start again. See How to fix a server that will not start.

Get your players set up

Players need the same loader and the same Minecraft version, and the mods that add content. They install them on their own computer.

1. Tell them your server's Minecraft version and loader.
2. They install that loader. The Fabric, Forge and NeoForge websites each have an installer for their loader.
3. They add the same mods to the mods folder of their game, or use a launcher that does it for them, such as the Modrinth App or the CurseForge app.
4. They join with your Server Address from Overview. See How to join your Minecraft server.

Not every mod must be on both sides. Modrinth marks each mod as client side, server side or both. A mod that only changes a player's screen, such as a map or a shader helper, belongs on the player's computer only. A mod marked server side only needs nothing installed on players' computers. A mod that adds blocks or mobs belongs on both sides. Read the environment on the mod's page before you install it, because putting a client-only mod on the server can crash it.

Update and remove mods

1. Open Modding, then Mods, then the Installed view.
2. A mod with a newer build shows both versions and an Update button. Updating replaces the mod file and removes the old one.
3. To remove a mod, open its ... menu and click Uninstall. Tick Also delete its configuration and data only if you are sure.
4. Restart the server.

Removing a mod that added blocks or items to your world can leave holes or missing items in worlds that used it. Take a backup first, and test on a copy if the world matters.

If an update changes the Minecraft version your mods need, update all of the mods that matter before you move the server. Players need the same updates.

Hybrid servers

Magma and Ketting try to run Forge mods and Bukkit plugins together. The panel marks them as advanced and less stable than a normal loader. Most servers do better with Fabric, Forge or NeoForge for mods, or Paper for plugins. See Minecraft server types explained.

Related

• How to reduce lag on your Minecraft server
• How much RAM does a Minecraft server need
• Minecraft server problems and fixes