Find your world
Valheim keeps worlds in %USERPROFILE%\AppData\LocalLow\IronGate\Valheim\worlds_local. Press Windows+R, paste that path and press Enter.
A world saved by a current version of Valheim is a folder named after the world. An older world is two files instead, <World name>.db and <World name>.fwl. Copy them somewhere safe before you start, so you always have your own copy.
Not there? The world is in Steam Cloud. In Valheim's world list, choose Manage saves, pick the world and move it to local first.
Upload it
- Set the world name. In your server's Settings, set World name to your world's exact name (letters, numbers, underscores and hyphens), press Save configuration and stop the server.
- Create an SFTP login. Open Files & SFTP and press Generate SFTP credentials. Do it after setting the world name: each login opens that world's folder.
- Upload the world. Connect with FileZilla or WinSCP and open valheim/worlds_local. Upload the world's folder there, keeping its name. For an older world, upload <World name>.db and <World name>.fwl to valheim/worlds_local instead.
- Start the server. Press Start. The server opens the world by its name, and backs it up every time it stops.
World modifiers and mods
Your world keeps the rules it was made with, such as combat difficulty or no build cost, until you set a world modifier preset, a modifier or a toggle in Settings. From then on, every start applies the rules set there.
If the world was played with BepInEx mods, set Server software to BepInEx and upload the plugins to BepInEx/plugins before you start. Every player needs the same client mods.