Install Forge on Your Minecraft Server

Updated June 10, 2026 · By Host Havoc Technical Support Team

Forge is a mod loader that lets you run Forge-compatible mods on your Minecraft server. The installation steps differ depending on which Minecraft version you are running. Use the reference table below to identify your version group, then follow the matching steps.

Before starting, connect to your server via FTP so you are ready to upload files.

Version and Java reference table

Minecraft versionJava versionJAR filenameMulticraft JAR option
1.1 - 1.11.2Java 8custom-1112below.jarCustom Jar File (MC 1.11.2 and Below)
1.12.X - 1.16.5Java 8custom.jarCustom Jar File (MC 1.12 to 1.16x)
1.17 - 1.17.1Java 16(libraries folder)Forge for Java 16+
1.18 - 1.20.5Java 17(libraries folder)Forge for Java 17+
1.20.6 - 1.21.xJava 21(libraries folder + shim)Forge for Java 21+

Forge for Minecraft 1.1 - 1.16.5 (Java 8)

  1. Visit the Forge download page and download the Installer for your target version.
  2. Run the installer JAR and select Install server. Choose a local folder for the files and click OK.
    Forge installer showing Install server option selected with folder path and OK button
  3. Connect via FTP and upload all contents from the local installation folder to your server's root directory.
    Windows Explorer showing the Forge installation folder contents ready to upload
  4. Rename the Forge JAR:
    • Minecraft 1.12.X - 1.16.X: rename to custom.jar
    • Minecraft 1.11.2 and below: rename to custom-1112below.jar

    Multicraft JAR File dropdown showing Custom Jar File options for different MC versions
  5. In the Minecraft panel, find JAR File and select Custom Jar File (MC 1.12 to 1.16x) or Custom Jar File (MC 1.11.2 and Below) as appropriate.
  6. Click Save and restart your server.

Forge for Minecraft 1.17 - 1.17.1 (Java 16)

  1. Visit the Forge 1.17.1 download page and download the Installer.
  2. Run the installer and select Install server. Choose a local folder and click OK.
    Forge 1.17 installer showing Install server option with folder selection and OK button
  3. In the installation folder, navigate to /libraries/net/minecraftforge/forge/[ForgeVersion]/.
  4. Copy unix_args.txt from that subfolder and paste it into the libraries folder (one level up).
    File Explorer showing unix_args.txt being copied from the ForgeVersion subfolder into the libraries folder
  5. Connect via FTP and upload the entire libraries folder to your server's root directory.
  6. In the Minecraft panel, find JAR File and select Forge for Java 16+.
    Multicraft JAR File dropdown with Forge for Java 16+ selected
  7. Click Save and restart your server.

Forge for Minecraft 1.18 - 1.20.5 (Java 17)

  1. Visit the Forge download page and download the Installer for your target version.
  2. Run the installer and select Install server. Choose a local folder and click OK.
    Forge 1.18+ installer showing Install server option with folder selection and OK button
  3. In the installation folder, navigate to /libraries/net/minecraftforge/forge/[ForgeVersion]/.
  4. Copy unix_args.txt and paste it into the libraries folder.
    File Explorer showing unix_args.txt being copied into the libraries folder for Forge 1.18
  5. Connect via FTP and upload the libraries folder to your server's root directory.

    Note: If you are running Forge 1.20.3 - 1.20.5, also upload the forge-1.2X-X.X.X-shim.jar file to the root directory.

  6. In the Minecraft panel, find JAR File and select Forge for Java 17+.
    Multicraft JAR File dropdown with Forge for Java 17+ selected
  7. Click Save and restart your server.

Forge for Minecraft 1.20.6 - 1.21.x (Java 21)

  1. Visit the Forge download page and download the Installer for your target version.
  2. Run the installer and select Install server. Choose a local folder and click OK.
    Forge 1.20.6+ installer showing Install server option with folder selection and OK button
  3. In the installation folder, navigate to /libraries/net/minecraftforge/forge/[ForgeVersion]/.
  4. Copy unix_args.txt and paste it into the libraries folder.
    File Explorer showing unix_args.txt being copied into the libraries folder for Forge 1.20.6
  5. Connect via FTP and upload the libraries folder to your server's root directory.
  6. Also upload the forge-1.2X-X.X.X-shim.jar file to the root directory.
  7. In the Minecraft panel, find JAR File and select Forge for Java 21+.
    Multicraft JAR File dropdown with Forge for Java 21+ selected
  8. Click Save and restart your server.

Troubleshooting

ProblemSolution
Server fails to start after installConfirm the correct JAR option is selected in Multicraft for your version group.
Mods not loadingEnsure mod files are in the /mods folder and compatible with your Forge version.
Wrong Java version errorCross-check the version table above and re-select the JAR option in Multicraft.