Free tool
Game world migration checker
Check your world before you move it to a dedicated server. Point it at your Valheim or Palworld save and it tells you whether the files a server actually needs are there, and what to fix before you upload them.
Your files stay in your browser. They are never uploaded, and no account is needed. The only thing we receive is an anonymous counter: which game you checked, the result category, and the issue codes. No file names, world names, seeds or contents.
Check a world
Drop your world files here
Both files of one world: <world>.fwl and <world>.db, with no _backup_auto- timestamp in the name. On Windows they live in %USERPROFILE%\AppData\LocalLow\IronGate\Valheim\worlds_local. If Steam Cloud is on, the live copy can instead sit in your Steam userdata/<id>/892970/remote/worlds folder, which is also where it lives on macOS.
What actually goes wrong when a world moves
Almost none of the failed migrations we see are corrupted saves. They are complete worlds uploaded with a piece missing, or a world that quietly brought settings from the machine it used to live on. Both are visible in the files before anything is uploaded, which is what this tool looks for.
The world is incomplete
A Valheim world is two files. Copy the .db without the .fwl, and the server does not report an error: it generates a new world and starts it, so the symptom is an empty map rather than a crash. Palworld is the same story one level up, where Level.sav without the Players directory keeps every base and Pal but drops every character.
The migration needs an action first
The world is fine, but something has to be decided before the server starts. Palworld's WorldOption.sav is the expensive one: it takes priority over the server's own config file, so a world exported from a co-op session can override the destination's name, password and advertised port. The server runs, direct connections work, and it never appears in the community browser. That one cost us a full day of debugging on a customer's server before we knew what to look for.
The format is not one we recognize
A newer game build can save a world in a format these rules have not been checked against. That is reported as unrecognized, never as corrupt, because the two look identical from outside and only one of them is your problem.
Why this runs in your browser
A save file is a personal thing, and answering this question does not need a server. The checker reads small slices of your files locally, builds the report on your machine and forgets it when you close the tab. Open your browser's network tab while you run a check: you will see no upload, because there is none. We deliberately do not read the whole .db or Level.sav either, so a 400 MB world is checked as fast as a new one.
Guides for the full move
Move the world once, to something that stays up
GHosting runs managed Valheim and Palworld servers with file access, a console and schema-driven settings, so uploading a world is a file transfer and a restart rather than a Linux project. Valheim has a free 48-hour trial, subject to capacity, and nothing renews automatically.
Common questions
Do my save files get uploaded anywhere?
No. The check runs in your browser: the files are read in small slices on your own machine and the report is built there. What we do receive is the same anonymous counter every page on this site sends, plus which game you checked, the result category and the issue codes, so we can tell whether the tool is useful. It never carries a file name, world name, seed, player id or any file content, and you can confirm all of that in your browser network tab.
What does "ready" actually mean?
It means you have the files a migration needs and none of the known traps apply, so the move is worth attempting. It is not a promise the world is undamaged or that the destination server will load it. Keep your source copy until the server has run once and you have joined.
Why does a Valheim world need two files?
The .fwl holds the world name, seed and format version. The .db holds everything that exists in the world. Upload only one and the server generates a fresh world around it, which looks exactly like losing your save.
Why does my Palworld server ignore the settings I set after moving a world?
A world hosted from the Palworld client carries WorldOption.sav, and Palworld reads that in preference to PalWorldSettings.ini. It is a complete settings store, so it also brings the old server name and advertised port, which is why a healthy server can be missing from the community browser while direct connections work.
Will my co-op character survive the move to a dedicated server?
The world does. The co-op host character does not, because a client-hosted world stores the host under a fixed identity while a dedicated server keys every player to their own account. Everyone else keeps their character. The host needs a separate migration.
Which games are supported?
Valheim and Palworld. Those are the two where a migration fails for reasons you can see in the files before uploading. More games follow once this one earns its keep.