Terraria Server Config: serverconfig.txt Explained Key by Key

A Terraria server config is one plain text file, serverconfig.txt, that answers every question the dedicated server would otherwise ask at start-up: which world, how big, how hard, which port, which password. This guide explains each key with the defaults from the official 1.4.5.8 server, and how they map to a hosted server.

New to running a server? Our free Terraria server guide covers the whole setup first. If you host with us, the main keys below are settings in the panel of your Terraria server.

• Format: one key=value per line; lines starting with # are skipped.
• Start it: TerrariaServer.exe -config serverconfig.txt, or ./TerrariaServer.bin.x86_64 -config serverconfig.txt on Linux.
• World: world loads a file, autocreate (1 small, 2 medium, 3 large) builds one if it is missing.
• Difficulty: difficulty 0 Classic, 1 Expert, 2 Master, 3 Journey. New worlds only.
• Access: password (empty for none), maxplayers (1 to 255) and port (7777).

How serverconfig.txt works

The Windows folder of the official dedicated server download ships an example serverconfig.txt and a start-server.bat that runs TerrariaServer.exe -config serverconfig.txt and starts the server again if it stops. The Linux and Mac folders have the server but no example file, so copy the Windows one.

The wiki's server page adds the rules that matter:

• The file can have any name. You point to it with -config, and relative paths are resolved from the folder that holds the server program.
• If you pass -config and the file is missing, the server falls back to asking every question in the console.
• Comment lines start with #. In the official example, every key is commented out except one, priority=1, so the file does nothing until you remove the # in front of the lines you want.

Without a config, the 1.4.5.8 server asks for the same values with its own defaults: "Max players (press enter for 16)", "Server port (press enter for 7777)", "Automatically forward port? (y/n)" and "Server password (press enter for none)". The keys below answer those questions in advance.

World size

Two keys decide which world the server runs:

• world= is the full path of a .wld file, for example C:\Users\YOU\Documents\My Games\Terraria\Worlds\world1.wld. With it, the server loads that world and starts without asking.
• autocreate= creates a new world when no file exists at that path. The example file defines 1 as small, 2 as medium and 3 as large.

The wiki's world size page gives the dimensions:

A large world has room for more of everything, but the same page notes that many small worlds can be more efficient than large ones because of the memory they need. For a group of four, medium is a sensible start.

Four more keys only act when autocreate builds a world:

• worldname= names the new world.
• seed= sets the seed text.
• seed_celebration, seed_theconstant, seed_notthebees, seed_notraps, seed_fortheworthy, seed_remix, seed_drunk and seed_zenith turn special world seeds on with 1. The example file says they override the seed text when enabled.
• worldpath= sets the folder where world files are stored.

The catch: autocreate never touches an existing world. Change the size or the seed and nothing happens until the file at world is gone and a new one is generated.

Difficulty

difficulty= sets the world mode, again only when autocreate creates the world. The example file lists 0 Classic, 1 Expert, 2 Master and 3 Journey.

Three points to keep in mind:

• Expert and Master start the moment the world is created and the player cannot change them later, except through the Journey difficulty slider.
• The Expert boss scaling matters on a server: the Expert Mode page explains that each extra player adds health to a boss, starting from 35% per player.
• The wiki's server page warns that mobile servers add 1 to the value, so on mobile 2 is Expert.

For Journey worlds, fifteen journeypermission_* keys decide who may use each power: 0 locks it for everyone, 1 lets only the host change it and 2 lets everyone change it. They cover freezing and setting the time, time speed, god mode, wind, rain, placement range, difficulty, biome spread and spawn rate. On a server with people you do not know well, 0 or 1 keeps one player from freezing time for the rest.

Password and slots

These are the keys that decide who can join:

• password= sets the password players type after the address. Leave it empty, or omit the line, for an open server.
• maxplayers= caps the number of players at once. The example file accepts 1 to 255. When the cap is reached, the next player sees "This server is full right now, please try again later."
• port= is the TCP port the server listens on, 7777 by default. If you change it, forward that port on your router and tell players to type it after the address.

You can check or change some of these while the server runs. The console commands password shows the password, password <pass> changes it, maxplayers prints the cap and port prints the listening port.

A player on another game version is refused with "You are not using the same version as this server." That message comes from the version, not from the config, so update the game or the server.

Other keys worth knowing

Everything else in the official example, with what the file itself says about each key:

Two notes. The wiki says UPnP "does not always work", so forward the port by hand if friends cannot connect. And to unban someone, the wiki's advice is to delete their name and IP address from the ban list file.

A few options exist only as launch parameters, not as keys. The example file's header lists -steam for Steam support, -lobby friends or -lobby private for who can join through Steam, -ip to choose the listening address and -noupnp to turn UPnP off.

A complete example

This is a small private server for four friends, built only from the keys above:

world=C:\Users\YOU\Documents\My Games\Terraria\Worlds\Friends.wld
autocreate=2
worldname=Friends
difficulty=1
maxplayers=4
port=7777
password=change-me
motd=Base is east of spawn
secure=1
language=en-US
npcstream=60
priority=1
journeypermission_godmode=0

Save it next to the server program, start with -config serverconfig.txt and the first run generates a medium Expert world called Friends. Every later start loads it again.

serverconfig.txt on a 1up server

On 1up you never edit the file by hand. The server rewrites it at every start from your panel settings:

• World size → autocreate (medium by default), Difficulty → difficulty (Classic by default), Seed → seed, Server password → password and Max players → maxplayers. Max players accepts 1 to 255, but the panel refuses a value above your plan's slots: 4 on Free, 8 on Casual, 10 on Starter and 20 on Pro (see pricing).
• The world is always worlds/world.wld, named after your server.
• The server listens on 7777 inside its container, but players connect to the public port the panel shows next to the address.
• Every journeypermission_* key is 0, so nobody can use Journey powers on a shared world.
• The rest is fixed: secure=0, upnp=0, language=en-US, npcstream=60 and priority=1.

Because the file is rebuilt at every start, hand edits in the file manager do not survive a restart. Change the settings in the panel and restart instead. The panel has no MOTD setting; you can still set one with the motd <message> console command, and it lasts until the next restart.

Tested on Terraria 1.4.5.8 (1up image sha256:d800f742, Vanilla template) on the 1up-servers platform, 2026-10-04; the official example file and prompts are from the 1.4.5.8 dedicated server download.

Change log

• 2026-10-04: first version.