Upload your Valheim world after 1.0

Valheim 1.0 (9 September 2026) changed how worlds are saved. Every host's old "upload the .db and .fwl" guide is now wrong, ours included. This is the version that works — on our servers and on anyone else's.

What changed

Before 1.0 a world was two files, YourWorld.db and YourWorld.fwl. Since 1.0 a world is a folder named after the world, and the data inside is split into pieces:

worlds_local/
└── YourWorld/
    ├── _main.0.fwl2      world metadata — seed, modifiers, name
    ├── _main.0.db2       core world data
    ├── _main.0.chunks    index of the terrain chunks
    ├── _main.0.ok        "this save finished" marker
    └── *.chunk           one file per explored piece of terrain

The number after _main. goes up with every save, and the .chunk files multiply as you explore. That is fine. The rule is simple: the folder is the world. Move the whole folder, always.

Why the server "made a new world" with a random seed and none of your modifiers A dedicated server starts whatever world name it is configured with. If no folder by exactly that name exists in worlds_local, it does not error — it quietly generates a brand-new world under that name. A fresh seed and missing modifiers means your upload was not found. Nine times out of ten it is one of the reasons in the troubleshooting list at the bottom.

1. Find your world on your PC

Worlds live in one of two places depending on whether Steam Cloud has them:

Local: C:\Users\YOU\AppData\LocalLow\IronGate\Valheim\worlds_local\YourWorld\
Steam Cloud: C:\Program Files (x86)\Steam\userdata\<id>\892970\remote\worlds\YourWorld\

If the folder is only in the Steam Cloud location, open Valheim, go to Manage Saves → Worlds, select the world and move it to local. Then use the local folder. Cloud copies can be partially synced, and a partial folder is a broken world.

On Linux the local path is ~/.config/unity3d/IronGate/Valheim/worlds_local/.

Close Valheim before you copy The last save has to finish first. If the newest _main.N.ok file is missing, the game was still writing — open the world once more, let it save, quit properly.

2. Old world from before 1.0? Convert it first

A 1.0 server ignores the old .db + .fwl pair and generates a new world with the same name. It does not convert them for you. The game client does:

Put YourWorld.db and YourWorld.fwl in your PC's worlds_local folder (the local path above).
Open Valheim → Manage Saves → Worlds. The world shows with an "old format" note.
Load it once in single player. Walk around for a few seconds, then quit to menu so it saves.
There is now a YourWorld/ folder next to the old files. That folder is what you upload.

3. Upload it to the server

These steps are the same on every host. On a YiorasHost server the file manager is in the game panel and the world name is on the Settings tab.

Stop the server. A running server autosaves over whatever you upload.
Open the server's worlds_local folder. On our panel: .config/unity3d/IronGate/Valheim/worlds_local.
If the server already generated a folder with your world's name (it will have, if you started it once), rename or delete that folder. Otherwise your files land next to the server's fresh ones and it keeps loading its own.
Upload the whole YourWorld folder. If your host only takes single files, zip the folder, upload the zip, extract it on the server, and delete the zip.
Check the result is worlds_local/YourWorld/_main.N.fwl2 (N is 0 or higher) — not worlds_local/YourWorld/YourWorld/… and not a zip sitting there unpacked. Nesting is the most common mistake after a zip upload.
Set the server's world name to YourWorld — exact same capitals. Servers are Linux; MyWorld and myworld are two different worlds.
Make sure the server is updated to 1.0. An older server build cannot read the new folder and will generate a new world. Ours update themselves on every start.
Start the server. Look for Game server connected in the console, then join.

Troubleshooting

Fresh world, random seed, modifiers gone — the server did not find your folder. Check, in this order: the world name matches the folder name including capitals; the folder is directly inside worlds_local and not nested one level deeper; a zip was actually extracted; the server's own generated folder with the same name was removed; the server is on 1.0.
The world loads but progress is old — you copied while Valheim was still open, or copied from Steam Cloud before it finished syncing. Copy again from the local folder with the game closed.
Terrain is missing or corrupt in places — some .chunk files did not make it. Delete the folder on the server and upload the complete one again. Never copy part of a world folder.
Old world still shows the "old format" note on the server — you uploaded the .db/.fwl pair. Convert it on your PC first (step 2) and upload the folder.
Modifiers are wrong even though the world loaded — modifiers live in the world's metadata, but some hosts also pass -modifier or -preset launch arguments, which override it. Clear those in the host's settings. We pass none.
Backups made before 1.0 do not restore — they contain the two-file format. Restore them to your PC, convert (step 2), upload the folder.

On a YiorasHost server and still stuck? Open a support ticket with your service name and the world name — we'll upload it with you.