What the .wld and .twld world files are, where they live on your server, and how to back them up safely so a bad update or mod change never costs you your world.
Your whole Terraria world lives in a couple of small files. Knowing which files matter, and getting into the habit of backing them up before anything risky, is the single best way to protect months of building.
What each file is
- WorldName.wld This is the world itself: the map, the terrain, your builds, chests and their contents, NPCs, everything. This is the file you cannot lose.
- WorldName.wld.bak A rolling backup that vanilla Terraria writes automatically. It holds the previous save, which can rescue you from a corrupted .wld, but it is only one save old, so do not rely on it alone.
- WorldName.twld On tModLoader, this companion file stores the modded parts of your world that vanilla cannot hold. A tModLoader world is really the pair .wld plus .twld, and they must be kept together.
The short version: on vanilla Terraria you care about the .wld. On tModLoader you must keep the .wld and the .twld together as a set, or the modded world data will not match.
Where to find them
- Open your server and go to the Files tab.
- Look in the server's worlds folder. It is commonly a Worlds folder, and the exact path is whatever your world= line in serverconfig.txt points to.
- You will see your .wld file there, its .wld.bak, and on tModLoader the matching .twld.
The easy way to back up: the Backups tab
GuavaHost gives every server snapshot backups built in.
- Go to the Backups tab.
- Click to create a backup. This captures your whole server, world files included, in one go.
- Restore any time by picking a snapshot. Remember that restoring overwrites the current files, so it rolls the world back to how it was at that point.
Always take a snapshot here before a risky change: updating tModLoader, adding or removing mods, editing config, or trying anything you are unsure about.
Keeping a copy on your own computer
It is smart to also keep a copy off the server now and then.
- Open the Settings tab and note the SFTP details (host, port, username). SFTP is a secure way to move files between your computer and your server.
- Connect with the free client FileZilla, or download the files straight from the Files tab.
- Download the .wld, and on tModLoader the matching .twld, and keep them somewhere safe. Grab both together so the pair stays complete.
Stop the server from the Console tab before copying the world off, so you capture a clean save rather than one mid-write.
Restoring a world you saved
- Stop the server on the Console tab.
- On the Files tab, upload your .wld (and .twld for tModLoader) back into the worlds folder.
- Make sure serverconfig.txt has world= pointing at that file.
- Start the server and watch the Console to confirm it loads.
Troubleshooting
- Modded world loads but modded content is missing or resets: you restored the .wld without its matching .twld. Put both back together.
- World will not load or looks corrupted: try the .wld.bak by renaming it to .wld, or restore a snapshot from the Backups tab.
- Changes did not save: the server may not have written the world yet. Stop it cleanly from the Console tab so it saves before you copy anything.
Still stuck? Jump into our Discord at discord.gg/GuavaHost and the team will help you out.