Free tools for your next playthrough

Terraria World Lab

Find the seed in your world. Plan something stranger for the next one.

Inspect a Terraria save, check whether tModLoader can open it, or put together a special-seed adventure for your friends. No account needed.

Your world files, names and seeds stay on this device. We receive anonymous usage counters, never your save or recipe contents.

01 / A new world

Build our next adventure

Choose the rules. Terraria generates the world when you run it.

Load a recipe

Your world recipe

Our next adventure

Server: Vanilla Terraria
World: Medium · Classic
Special seeds: None
Seed: Random when generated

Keep this recipe in the current browser tab. Start a server or a no-card 48-hour trial, choose the same server type, then open Worlds to review and create it.

For a server you host yourself

Use these generation options in your server config. Set world= to a new, unused file path and create its parent folder first. Ports, passwords and other settings are yours to keep.

# Terraria World Lab: world generation options
# Set world= to a NEW, unused .wld path on your server. Create its parent folder first.
# These settings do not change a world that already exists.
world=worlds/our_next_adventure.wld
autocreate=2
worldname=Our next adventure
difficulty=0

02 / A world you already have

Inspect my world

Find its seed, size, difficulty and special seeds. Check which server can open it before moving your save.

Check a world

Drop your world files here

The world's .wld file. For a tModLoader world, add the .twld with the same name too. On Windows they are in Documents\My Games\Terraria\Worlds, or tModLoader\Worlds under the same folder for modded worlds. If a world is saved to Steam Cloud, click its cloud icon in Terraria's world list first to keep a copy on your PC.

From a recipe to a real server

A new playthrough. Your old world, kept.

The Worlds tab creates, uploads and switches worlds. Try Zenith with friends, then switch back to the world where your base lives. Creating a world never replaces the ones already there.

Explore Terraria hosting →Read the special-seed setup guide →

Our Terraria adventuresPanel preview

Worlds

One world running. The rest, ready when you are.

Create a world +

Running nowOur Zenith challenge

Medium · Master · Zenith

Active world

Kept on the serverThe world with our base

Medium · Classic · Corruption

Switch to this →

Example worlds in the Worlds tab. Creating or switching restarts the server.

Terraria seeds and world files, explained

How do I find the seed of my Terraria world?

Select the .wld in Inspect my world below. The checker reads the seed from the file header on your own device. It also shows size, difficulty and special seed flags. It does not upload the file.

Can I combine Terraria special seeds on a dedicated server?

On current vanilla servers, yes. Each selected special seed is written as a seed_<name>=1 setting. Zenith already includes seven special seeds, but not Skyblock. tModLoader currently accepts one special seed as seed text; combinations and Skyblock are not available there yet.

Does the builder generate a world or show its map?

The builder prepares the options. Terraria generates the actual world when a server starts with a new, unused world file path. It does not predict terrain, chest loot or a map from a seed.

Can tModLoader open a vanilla Terraria world?

That depends on the version which saved the world. The inspector compares its header with the server versions GHosting measures in daily verification. tModLoader cannot open a world saved by a newer Terraria than it runs.

Can I change the size or difficulty of an existing world?

Generation options only apply to a new world. On GHosting you can create a different world in the Worlds tab and keep the old one to switch back to later.

Do I need an account, and what is tracked?

No account is needed for the lab. World files, names, seeds and recipe contents stay in your browser. We receive anonymous page and button counters, plus the result category and known issue codes from world checks. Choosing to create or upload a world on your own GHosting server is a separate action.