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Using a custom JAR is easier than ever on Multicraft! The following steps will show you how to install your custom JAR file and set the server to run using that file.

Head over to your FTP File Manager either via an FTP Client such as FileZilla or by using our Web FTP viewer.

Upload the JAR file that you would like to use.

Rename the JAR file to custom.jar

Go to your server dashboard and click "Change server version"

Select "Other" from the list of categories on the sidebar

Now you can select whether you want your JAR to run on Java 8, Java 11 or Java 16

Ensure that your JAR supports your chosen Java version. Java 16 is required for JARs that run on Minecraft version 1.17 or higher, and in a lot of cases not supported for versions below 1.17

Now select "Custom JAR (Java (version)) (Rename JAR to custom.jar)" and click "Save Option"

Reboot your server and you are good to go!

If you are having any troubles with installing your custom JAR file. Open a support ticket or join our discord at
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