How to Reset Your Minecraft World or Change the Seed

To reset your Minecraft world or use a new seed: stop the server, delete the world folder(s) in Files, set your seed in Server Properties, then start the server. It will generate a brand-new map using that seed. The mistake most players make is deleting the wrong folder or skipping a backup first, do both of those and this is a five-minute job.

Symptoms

• You want a fresh map, a specific seed, or to switch from hardcore to normal (or back)
• Your modpack update left the world in a broken or laggy state
• You're moving from a modded server to vanilla and want a clean slate
• A world reset was done, but items, builds, or progress unexpectedly disappeared

Why this happens

Minecraft doesn't "regenerate" a world in place. The seed only controls how new terrain is generated. It has no effect on chunks that already exist on disk. So to actually see a new seed in action, the old world data has to be gone before the server boots. That's why every reset is really two steps: clear the old world folder, then make sure the seed value is set the way you want before the server creates the new one.

How to fix it

1. Back up first. Go to Backups and take a snapshot before touching anything. If the new world isn't what you wanted, or you deleted the wrong thing, this is your way back.
2. Click Stop on the server's top bar to shut it down completely.
3. Open Server Properties and set the seed field to your desired seed. Leave it empty for a random world.
4. Go to Files and delete the world folder (and its nether/end companions if present). Double-check you're deleting the live world, not a backup or renamed copy sitting nearby: deleting the wrong folder is the single most common way players lose their builds permanently.
5. Click Start. The server will generate a fresh world using the seed you set.
6. If you're on a modded server, confirm your mods are still compatible with a freshly generated world: some world-generation mods (biome or dimension packs) can fail on a brand-new map. Check the Fix "Missing Dependency" and Mod Conflict Errors guide if the server won't come back up.

Never delete a folder you're not 100% sure is the active world. If it's named oddly (world1, world_old, etc.), treat it as a possible backup and leave it alone until you've confirmed otherwise.

If you're resetting because you're switching modpacks entirely rather than just changing the seed, see How to Install a Modpack on Your Minecraft Server instead. That process handles the world/version swap for you.

Still stuck?

If the server won't start after you delete the world, open Console and read the crash output. It will usually name the mod or setting at fault. Our Minecraft Server Won't Start: How to Read the Crash Log guide walks through the common causes. If you deleted the wrong folder and don't have a backup, or the seed field isn't behaving as expected, open a support ticket and our team can check the panel directly.

Before your next reset, get in the habit of using How to Back Up and Restore Your Server first. It's the difference between a five-minute redo and a permanent loss.