You don’t have to start over. Whether you have a singleplayer world you want to share or a LAN world or a server you’re moving from another host, open your server’s World tab and use Import world data. Levyathan understands normal Java world ZIPs, maps singleplayer DIM-1/DIM1 folders to the Nether and End, and creates a registered safety backup before changing anything.
Understand the world folder
A Minecraft server keeps its world in a folder named, by default, world - with separate world_nether and world_the_end folders for the other dimensions. Inside world are level.dat (the world’s metadata and seed) and the region/ folder (the actual chunks). A singleplayer save (in .minecraft/saves/<name>) has the same structure, just with the Nether and End nested inside it. A LAN world is the same Java save format as a singleplayer world.
Move a singleplayer world
- 1Create a Levyathan server on the SAME Minecraft version your world was last opened in. This matters - see the warning below.
- 2Find your save: .minecraft/saves/<YourWorld> (Windows: %appdata%\.minecraft\saves). Zip its contents.
- 3On Levyathan, open the World tab and choose “Upload a dimension”. Select Overworld and upload the ZIP. Stop the server first; the import button stays disabled while it is running.
- 4If you want all three dimensions at once, choose “Replace entire server”. Levyathan maps DIM-1 and DIM1 automatically and keeps its managed server program, ports, RCON and EULA files.
- 5Start the server and join - you should spawn in your world.
Move from another host
- 1On the old host, stop the server and download its world, world_nether and world_the_end folders (or a full file backup).
- 2On Levyathan, match the Minecraft version, stop the server, then use “Replace entire server” in the World tab. The import brings over customer-managed worlds, plugins, mods and configs while keeping Levyathan’s managed runtime and network files.
- 3If you only want the world, choose “Upload a dimension” instead. Reinstall plugins from the Plugins/Mods tabs when you want Levyathan to resolve versions and dependencies for you.
- 4Start and verify.
The version rule (read this)
Minecraft upgrades a world’s data format when a newer version opens it, and that upgrade is often one-way. Loading a 1.20 world on a 1.21 server will convert it; loading a newer world on an older server simply won’t work. Always set the Levyathan server to the version your world came from, and if you do intend to upgrade, take a backup first so a bad conversion isn’t permanent. The level-name line in server.properties must also match your world folder’s name (it’s world by default).
Always back up first
The importer creates a registered safety backup before applying the replacement. If an upload goes wrong or the version conversion misbehaves, restore that backup and try again.