Fabric 23w13a_or_b Server Jar Download

Experimental — snapshot Official source

The Fabric server launcher for Minecraft 23w13a_or_b uses Fabric Loader 0.20.1 and installer 1.1.2; on first start it downloads the vanilla 23w13a_or_b server from Mojang. It requires Java 17 or newer.

Download

Download Fabric server launcher178 KB

Downloads from meta.fabricmc.net — Official — FabricMC.

The upstream does not publish a checksum for this file. MCJarHub computes a SHA-256 for such files on a schedule and shows it here once available — see how we source & verify.

Source: Official — FabricMC No checksum published yet Last checked: 28 Oct 2026, 12:46 UTC Report a problem

Version facts

Minecraft release date	1 Apr 2023
Channel	Preview (april)
Required Java	Java 17 or newer · Temurin 17
Fabric Loader	0.20.1
Fabric installer	1.1.2
Fabric API (mod)	0.76.3+23w13a_or_b
File size	178 KB
Licence	Apache-2.0
Upstream project	fabricmc.net

What changed

Fabric Loader 0.20.1 release notes What's new in Minecraft 23w13a_or_b (Minecraft Wiki)

Compatibility

Loads Fabric mods for Minecraft 23w13a_or_b; most need Fabric API 0.76.3+23w13a_or_b in the mods/ folder.

Players need a Minecraft: Java Edition 23w13a_or_b client on the same version.

Minecraft 23w13a_or_b in other server software

Snapshot Quilt

Known issues & safety notes

Preview builds are experimental: they can corrupt or irreversibly upgrade worlds, and most plugins and mods do not support them yet. Test on a copy of your world.
Known issues: search Fabric's issue tracker for 23w13a_or_b

How to set up Fabric 23w13a_or_b

Install Java 17 or newer (e.g. Eclipse Temurin) and check it with java -version.
Download the Fabric server launcher above (about 178 KB) into an empty folder.
Start it with the script below. On the first start the launcher downloads the vanilla 23w13a_or_b server from Mojang and the Fabric libraries — this needs internet access.
Accept Mojang's EULA in eula.txt (eula=true) and start again.
Put mods into mods/. Most mods need Fabric API 0.76.3+23w13a_or_b there too.

Linux / macOS — `start.sh`

#!/bin/sh
# start.sh — Fabric 23w13a_or_b
cd "$(dirname "$0")"
JAVA_MAJOR=$(java -version 2>&1 | awk -F'"' '/version/ {split($2, v, "."); print (v[1] == "1") ? v[2] : v[1]}')
if [ "$JAVA_MAJOR" -lt 17 ] 2>/dev/null; then
  echo "Java 17 or newer is required (found Java $JAVA_MAJOR)."
  exit 1
fi
java -Xms6G -Xmx6G -jar fabric-server-mc.23w13a_or_b-loader.0.20.1-launcher.1.1.2.jar nogui

Windows — `start.bat`

@echo off
REM start.bat — Fabric 23w13a_or_b
REM Needs Java 17 or newer: run "java -version" to check.
java -Xms6G -Xmx6G -jar fabric-server-mc.23w13a_or_b-loader.0.20.1-launcher.1.1.2.jar nogui
pause

Modded servers need more memory: 6–8 GB for a light modpack, 8–12 GB or more for large packs. Leave 1–1.5 GB for the operating system. How much RAM?

Docker

docker run -d -p 25565:25565 -e EULA=TRUE -e TYPE=FABRIC -e VERSION=23w13a_or_b --name mc itzg/minecraft-server

Uses the community itzg/minecraft-server image, which downloads the file itself.

Upgrading

FAQ

What Java version does Fabric 23w13a_or_b need?

Fabric 23w13a_or_b needs Java 17 or newer. Running it on an older Java fails with an UnsupportedClassVersionError mentioning class file version 61.0.

Is Fabric 23w13a_or_b safe for my survival world?

Only on a copy. Preview versions are experimental and upgrade worlds irreversibly; keep a backup and don't switch a live world to a snapshot, pre-release or release candidate.

Why is the Fabric server file so small?

It is only a launcher. On the first start it downloads the vanilla Minecraft 23w13a_or_b server from Mojang and the Fabric Loader libraries.