How to Use Valheim Seeds to Create Custom Worlds

Like Yggdrasil, a world in Valheim begins from a single seed, and picking one yourself puts you in charge of where the starting island, biomes, and bosses land before you even reach Valheim. A seed only shapes brand new worlds, though, so bringing your chosen layout onto your server takes one extra step: build it locally first, then move the files across. In this Nitrado guide, we’ll show you how to generate a custom Valheim world with a seed of your choice and get it running on your server.

Can You Set a Custom Seed Directly on a Server?

Valheim servers support worlds generated from a custom seed, but there’s no field for entering one directly on a dedicated server. Instead, you create the world in single-player using the seed you want, then upload the finished world files to your server afterward.

A seed only reproduces the same layout for the world-generator version it was created under, and Iron Gate has changed generation with major updates before. With Valheim 1.0, a world you create fresh generates all the newest content right away; an existing world only grows new content into the areas you haven’t explored yet.

Create Your Custom World in Single-Player

1. Open Valheim, then select Start Game. Choose an existing character, or create a new one.
   
2. On the Select World screen, select New, enter a name for your world and type in your chosen seed. Afterward select Done.
   
3. Select Start to load into your new world.

The following steps only matter if your world is still sitting in Steam Cloud. Skip them if they are already saved locally.

1. Open Manage Saves, then open the Worlds tab.
   
2. Select your new world, then choose Move to Local so the files save to your PC. This step only matters if the world is still sitting in Steam Cloud; skip it if the world already saves locally.
   

Confirm the world looks the way you want. You can use a third-party tool like Valheim.Tools to see the entire map of the seed. If it doesn’t, back out to the main menu and repeat these steps with a different seed. A world’s seed shows on the Select World screen next to its name, so you can note down ones worth trying again later.

Upload Your Custom World to the Server

A Valheim world save is now a whole folder instead of two loose files.
On your PC, open:
C:\Users\<username>\AppData\LocalLow\IronGate\Valheim\worlds_local
and find the folder matching your world’s name; it holds every .chunk, .chunks, .db2, .fwl2, and .ok file the server needs.

1. Upload that whole folder into valheim/savedata/worlds_local on your server, either through an FTP client or by creating a matching folder in the File Browser under Tools in your Nitrado web interface and uploading the files into it.
2. Open Settings > General, set the World name field to match your world folder’s name exactly, select Save Changes, then restart the server.

For the full detailed walkthrough on both upload methods, including troubleshooting a name mismatch, see our guide on uploading an existing world to your Valheim server.

Set Sail for New Shores

Your world with custom seed is ready, and your adventure in Valheim can begin. Gather your vikings, set out from your chosen starting point, and see where the world takes you. Test out different seeds to explore completely uncharted territories!