Map seed vs world seed — is there a difference?
Search "Valheim seed" and you'll see the terms map seed, world seed and just seed used interchangeably. Confusingly, that's mostly correct — but there are two genuinely different things people mean, and knowing the difference saves arguments.
One string, one world
In Valheim there is only one kind of seed: a string of up to ten characters that seeds the
world generator. "World seed" and "map seed" are the same thing wearing different names. Type
HB7sK9pqWu into a new world or into a seed viewer, and both produce the same
planet — same biomes, same boss altars, same Haldor. The game even accepts numbers: entering
digits is fine, and the game converts them the same way every time.
Where the confusion comes from
- Map tools say "map seed" because they draw maps; the game says "world seed" because it makes worlds. Same input.
- Screenshots lie over time. Generation rules changed with the 1.0 update — most notably the far north, now the Deep North. A seed's map from a 2023 guide and the same seed on 1.0 match almost everywhere except the new northern content. The string didn't change; the rules did.
- Old worlds keep old rules. Your pre-1.0 save isn't converted. New rules apply to worlds created on 1.0.
What is genuinely NOT decided by the seed
A seed decides the terrain and structure placement — not your loot, not mob spawns you've already fought, and not anything about your buildings. Chest contents and drops roll while you play. So two friends entering the same seed will share geography but not identical item luck.
Case sensitivity: the real trap
Seeds are case sensitive. hb7sk9pqwu and HB7sK9pqWu are different
worlds. Copy the string exactly, and when sharing, prefer a
seed viewer link that carries the seed in the URL — no typing errors possible.
Bottom line
Map seed = world seed = the seed. What matters in 1.0 is that your tool follows the current generation rules — ours does, and our 1.0 Deep North guide explains exactly what changed for old favorites.