How to Install Minecraft Mods and Make a Modded Server (Fabric)

Applies to: Minecraft: Java Edition 26.3 with Fabric Loader 0.19.5 (tested with Fabric API 0.161.0, Lithium 0.26.2 and Chunky 1.5.3)

Mods change or extend Minecraft: Java Edition. They need a mod loader, and every mod is made for one loader and one Minecraft version. This guide uses Fabric; the idea is the same for NeoForge or Forge. Bedrock Edition doesn’t use mods (it has add-ons).

1. Choose the loader

• Fabric: lightweight and quick to update to new Minecraft versions. Most mods need Fabric API.
• NeoForge and Forge: used by many large mods and modpacks.

Pick the loader your favourite mods or modpack are made for. Mods for different loaders can’t be mixed.

2. Download mods from trusted sites

Use Modrinth or CurseForge, and pick the file for your Minecraft version (here 26.3) and your loader. Avoid re-upload sites: modified .jar files are a common way to spread malware.

3. Install on your computer

1. Install Fabric (see install Fabric).
2. Copy the mod files and Fabric API into the mods folder (Windows: %appdata%\.minecraft\mods).
3. Start the Fabric installation in the launcher.

4. Make a modded server

Put the same mods into the server’s mods folder. We downloaded Fabric API and Lithium for 26.3 straight onto the server:

cd ~/fabric/mods
curl -sSLO "https://cdn.modrinth.com/data/P7dR8mSH/versions/bNnaTiuM/fabric-api-0.161.0%2B26.3.jar"
curl -sSLO "https://cdn.modrinth.com/data/gvQqBUqZ/versions/xS0Q8LSi/lithium-fabric-0.26.2%2Bmc26.3.jar"

(Copy the current download links from each mod’s page.) After a restart the log listed Loading 44 mods, including fabric-api 0.161.0+26.3 and lithium 0.26.2+mc26.3. The number is higher than the number of files because Fabric API is made of many small modules.

• Client-only mods (shaders, minimaps, performance mods such as Sodium) don’t belong on the server.
• Server-side mods (Lithium, world pre-generators such as Chunky) can run on the server alone.
• Content mods (new blocks, items, mobs) must be on both server and every player.

When a mod is missing a dependency

We added Chunky without Fabric API. Fabric refused to start and explained why:

Incompatible mods found!
A potential solution has been determined, this may resolve your problem:
	 - Install fabric-api, any version.
More details:
	 - Mod 'Chunky' (chunky) 1.5.3 requires any version of fabric-api, which is missing!

Add the missing mod (or the version it asks for) and start again.

Troubleshooting

• Read logs/latest.log and the crash-reports folder; the first error is usually the useful one.
• Check that every mod matches the Minecraft version and loader.
• Remove recently added mods one at a time to find the one that breaks the game.
• Back up the world folder before adding or removing mods: removing a content mod deletes its blocks from the world.

Modpacks are easiest with a launcher that installs them for you; many modpacks also offer a ready-made “server pack”. Mods need more memory than the plain game: give Minecraft more RAM. Let players in: open the server port. Our Minecraft VPS engineers can set up modded servers for you, billed by time.

Official documentation: Fabric: installing mods.