How to Install a Fabric Server

Updated · MCJarHub

Download the Fabric server launcher for your Minecraft version, run it with java -Xmx4G -jar fabric-server-launch.jar nogui (use the real file name), accept the EULA, then put Fabric API and your mods into the mods/ folder.

What you download

Fabric's official server download is a small launcher (around 180 KB), built by Fabric's meta service for one Minecraft version, one Fabric Loader version and one installer version. On the first start it downloads the vanilla Minecraft server from Mojang and the Fabric libraries, so the server needs internet access the first time.

Current example: Fabric for Minecraft 26.3 with Loader 0.20.1 — matching Fabric API: 0.165.0+26.3. All versions are on the Fabric download page.

Step by step

  1. Install the Java version your Minecraft version needs (table) and check it with java -version.
  2. Create an empty folder and download the Fabric server launcher for your Minecraft version into it.
  3. Start it: 
    java -Xms4G -Xmx4G -jar fabric-server-mc.26.3-loader.0.20.1-launcher.1.1.2.jar nogui
    The launcher downloads server.jar and the libraries, then stops because the EULA is not accepted yet.
  4. Open eula.txt, set eula=true and start again. The server creates the mods/ folder.
  5. Download Fabric API for the same Minecraft version (from Modrinth or CurseForge) and put it into mods/ — most Fabric mods need it.
  6. Add your mods to mods/, restart, and check the log: missing or incompatible dependencies are listed by name.

Which mods go where

  • Content mods (new blocks, items, mobs, dimensions) must be installed on the server and by every player, in matching versions.
  • Server-side-only mods (for example performance, backups, administration) are installed only on the server; vanilla clients can join.
  • Client-only mods (shaders, minimaps, UI tweaks) don't belong on the server — some refuse to load there.

Players install Fabric with the official Fabric installer for their launcher and use the same Loader and Minecraft version as the server.

Updating and troubleshooting

  • To move to a newer Loader, download a new launcher for the same Minecraft version and replace the old one. Changing the Minecraft version also means updating every mod — see updating safely.
  • UnsupportedClassVersionError: wrong Java — fix.
  • The first start fails without internet access: the launcher must reach Mojang and Fabric's maven once.
  • Memory: modded servers need more than vanilla — see how much RAM.

Deciding between loaders? Read Fabric vs Forge vs NeoForge. Quilt, a Fabric fork, uses an installer instead — see the Quilt page.

FAQ

Do I need Fabric API on the server?
Most Fabric mods require it. Download the Fabric API version that matches your Minecraft version and put it in mods/ next to the other mods.
Do players need the same mods?
For mods that add content (blocks, items, mobs) yes. Server-side-only mods such as performance mods don't need to be installed by players.