Valheim World Generator Guide 2026: Create Custom Worlds

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How to preview a Valheim seed before you play, what makes a good world, which world modifiers exist, and how to get the seed you picked onto a dedicated server.

Valheim key art with two Vikings at a campfire in a dark forest

Valheim builds a different map for every seed. A map viewer lets you look at that map before you commit to it, and the world modifiers change how hard the world plays. Here is how to use both, and how to get the seed you picked onto a server. Once you have a layout you like, you can run it for your whole group on Valheim server hosting.

How Valheim World Generation Works

Every Valheim world generates from a text seed. According to the Valheim Wiki, the same seed gives the same layout for any given game version: terrain, biomes, boss altars and dungeons. Haldor the trader is the exception, because a world has several possible spots for him (more on that below). Change one letter in the seed and you get a different world.

The game builds the contents of each zone the first time a player comes near it; the wiki's Haldor page, for example, says his camp is placed when its zone is generated, a few hundred metres before you reach it. That is why Iron Gate's 1.0 FAQ says that in a world made before 1.0, the new biome generation only works properly in areas nobody has explored yet.

Using a World Generator Tool

A browser map viewer draws the whole world for a seed without launching the game. The one we point people to is valheim-map.world, and our Valheim map viewer guide goes through it step by step. The short version:

  1. Enter the seed
  2. Leave World Version on the newest option, the default: 1.0.7 on 31 October 2026, which covers every world made since the 1.0 release
  3. Look over the biomes, the boss altars, Haldor's possible spots and the crypts
  4. Write down the seeds worth keeping

World Version means the version a world was created on, not the patch you play, so do not look for 1.0.21 (the latest patch, 28 October 2026) in the list. For a world from before 1.0, the viewer's help says to open it once in Valheim 1.0 and upload its save files instead, because that first load reshuffles an old world's unexplored locations.

It saves you hours of sailing just to find out what a world looks like.

What to Look For in a Good World

When evaluating generated worlds:

Starting Area: A large Meadows biome near spawn with nearby Black Forest gives you room to build and access early game resources without long travel.

Biome Accessibility: The biomes you need early (Meadows, Black Forest, Swamp, Mountain, Plains) should be within a reasonable sail. The Ashlands sit at the southern edge of the world and the Deep North at the northern edge, so those two are a long trip on every seed. Compact worlds are easier to get around.

Boss Altar Locations: Check that the boss altars are spread sensibly. If the early ones are each on a different far-flung island, progression turns into more sailing than fighting.

Trader Position: A world has 10 possible spots for Haldor the trader, all in Black Forest, and he settles at the first one anyone approaches, according to the Valheim Wiki. If every possible spot is on the far side of the map, reaching him early is difficult. Since Valheim 1.0 he also sells inventory upgrades (Deeper Pockets and Wider Pockets, per Iron Gate's 1.0 patch notes), so a trader near spawn is worth more than it used to be.

Coastline and Islands: Worlds with a central continent and nearby islands offer the best experience. Worlds that are entirely fragmented into tiny islands make overland travel impossible.

World Modifiers (In-Game)

Valheim's official world modifiers are on the world select screen in game. You can pick a preset (Easy, Hard, Hardcore, Casual, Hammer mode or Immersive) or set each one yourself:

  • Combat: how much damage players and enemies deal, enemy speed and size, and how often enemies spawn with stars
  • Death penalty: from keeping your equipped gear to losing every item and all skills
  • Resource rate: from 0.5x to 3x the normal drops
  • Raids: from none at all to more frequent than normal
  • Portals: from letting every item through to no portals at all
  • Switches for no build cost, passive enemies, player based raids, no map and fire hazards

They apply to everyone who plays on that world. The Valheim Wiki's world modifiers page has the exact numbers behind each setting. On a dedicated server you set them with launch options, which Iron Gate's server guide lists as -preset, -modifier and -setkey.

Custom World Generation with Mods

Mods can change world generation further than the base game allows. One example is Better Continents, which improves the standard terrain generation and can override parts of it with image maps, for control over height, biomes, location placement and forest coverage. Its original Thunderstore listing is now marked deprecated and names a fork by Wubarrk on another mod site as the version to use instead.

A world made with it needs the mod wherever it runs. The mod's setup guide says the server and every player need the same version of Better Continents, and the server needs the extra .BetterContinents file uploaded along with the world. It runs on BepInEx. Iron Gate has no official mod support (its 1.0 FAQ says so plainly), so check that a mod has a release for 1.0 before you build a world on it. valheim-map.world does not support mods that change world generation either, so you lose the preview.

Using Seeds on Dedicated Servers

The Valheim dedicated server has no seed setting. Start it with a world name it has never seen and it makes a new world with a random seed. The Valheim Wiki's dedicated server page describes the same workaround we use. To play the seed you picked:

  1. Create the world in Valheim on your own PC with that seed and load into it once, so the game saves it.
  2. Upload it to the server's worlds folder. Since 1.0 a world is saved as a folder named after the world, so upload the whole folder. A world from before 1.0 is a .fwl and .db pair; the game converts it to the new format the first time it loads it and makes a backup first.
  3. Set the server's world name to the world's name exactly (the name, not the seed) and restart.

If the names do not match, the server makes a fresh random world instead. For community servers, choosing the seed in advance lets you plan spawn locations, base spots, and event areas before players join.

Sharing Seeds

The Valheim community shares recommended seeds online. When using a shared seed:

  • Verify it was tested on your game version (updates can change generation)
  • Screenshots from the sharer help confirm what you should expect
  • The world modifier settings must also match if they shared with specific modifiers

FAQ

What is a Valheim world seed? A text string that determines the world layout. The same seed gives the same layout on the same game version; only Haldor's camp depends on which of his possible spots someone reaches first.

Can I change the seed of an existing world? No. The seed is fixed at creation. You would need to start a new world with the different seed.

Do world generators show everything? No. valheim-map.world shows the biomes, the coastline and points of interest such as Haldor's possible spots, the boss altars and dungeons. It does not show ore, Finewood or Thistle (the site says that vegetation layer takes far too long to calculate for a whole world) or the Sea Serpent, which is a random spawn around players.

Can I set a seed on a Valheim dedicated server? Not directly. Create the world with that seed on your PC, upload it, and set the server's world name to match.

Related: Valheim map viewer guide, Valheim best seeds, Valheim dedicated server setup

Sources

All opened on 31 October 2026: