How do I pregenerate the Nether and End?

Select the world with chunky world—for example, chunky world world_nether or chunky world world_the_end—then start generation with chunky start.

Why is my server under heavy load while pregenerating?

Pregeneration constantly loads and saves new chunks, which uses a lot of CPU and RAM. Generate in manageable steps, preferably when nobody is playing, to avoid exceeding your resource limit for an extended period.

Can I use Chunky for Minecraft Bedrock Edition?

No. Chunky is only available for the Minecraft Java Edition.

Minecraft: Pregenerate Your World (Chunks) with Chunky

Pregenerate chunks with Chunky: Learn how to pregenerate your Minecraft world on Paper, Spigot, Fabric, or Forge to avoid lag → Find out more

10 November 20266 min read0 Views0 helpful

Introduction

When players explore new areas, your Minecraft server has to generate the chunks there on the spot. This uses a lot of CPU and RAM and can quickly cause lag, especially when several players are exploring at the same time. A better option is to generate the world in advance (pregenerate it). This way, the chunks are already stored on disk and only need to be loaded while players are playing.

Minecraft doesn’t include a feature for this. The easiest way is to use Chunky, a free chunk pregenerator available as both a plugin and a mod. This guide explains how to install Chunky on your game server, pregenerate your world, and use its commands.

Minecraft: Pregenerate Your World (Chunks) with Chunky

Before you start

Chunky doesn’t work on a pure Vanilla server. It requires a server type that loads plugins or mods:

Server type	Chunky as	Tab in the web interface
Paper, Spigot, Purpur	Plugin	Plugins
Fabric, Forge, NeoForge	Mod	Mods

If your server is currently running Vanilla, switch the server type under Games & Variants. Our guide to Switching Games explains how. For pregenerating only, we recommend Paper: Paper generates chunks much faster than Vanilla or Spigot.

Info

Each variant has its own data folder on your server. For example, if you switch from Vanilla to Paper, Paper will initially start with a new world. To keep using your existing world, transfer it as described in Adding Your Own World.

Info

Chunky is only available for the Java Edition. You can’t use Chunky for Minecraft Bedrock Edition.

Install Chunky

As a plugin (Paper, Spigot, Purpur)

Open your game server’s management page and go to the Plugins tab.
Search for Chunky in the plugin browser and install it with one click.
Restart your server to load the plugin.

Alternatively, download Chunky from Modrinth, Hangar, or SpigotMC and place the .jar file in the plugins folder. Find out more in our guide to the Plugin Uploader.

As a mod (Fabric, Forge, NeoForge)

Open your game server’s management page and go to the Mods tab.
Search for Chunky in the mod browser and select the version that matches your Minecraft version and mod loader.
Chunky also requires the Fabric API on Fabric. The mod browser will show you any required dependencies. Install the Fabric API as well if it isn’t already installed.
Restart your server.

Alternatively, download the mod from Modrinth or CurseForge and place it in the mods folder. Our guide Installing Mods / Modpacks shows you how to do this step by step.

Check the installation

Open the Console tab and enter chunky. If a help overview with all commands appears, Chunky is installed correctly.

Pregenerate your world

The easiest way to enter Chunky commands is directly in your game server’s Console, without a slash. If you’re an operator, you can also use them in-game, with a / in front—for example, /chunky start.

Set the area and start

First, choose the area to generate. If you don’t make a selection, Chunky uses a square around the point 0 0 with a radius of 500 blocks. To use a radius of 5,000 blocks around the center of the world, enter these commands one after another:

Code

chunky center 0 0
chunky radius 5000
chunky start

Instead of chunky center 0 0, you can use chunky spawn to set the world spawn as the center. If you’ve already set a world border, chunky worldborder uses its center and radius.

You can also use abbreviations for the radius: chunky radius 10k means 10,000 blocks, and chunky radius 625c means 625 chunks.

Tip

It’s best to start with a smaller radius, such as 5,000 blocks, and expand it later—for example, with chunky radius +2k. The world size increases very quickly as the radius grows, so the time required and storage space needed increase accordingly. Chunky simply skips chunks that have already been generated when you start it again.

Pregenerate the Nether and End

Chunky always works with the currently selected world. To pregenerate the Nether and End, select each world and start the process again:

Code

chunky world world_nether
chunky start
chunky world world_the_end
chunky start

On Paper and Spigot, the worlds are usually named world, world_nether, and world_the_end. On Fabric, Forge, and NeoForge, the dimensions are usually named overworld, the_nether, and the_end. If you’ve set a different level-name in server.properties, the name of the Overworld will also be different.

Check progress, pause, and cancel

While generating, Chunky continuously reports progress in the console: chunks processed, percentage complete, estimated time remaining (ETA), and the rate in chunks per second. In-game, chunky progress shows you the current status.

chunky pause pauses generation and saves your progress.
chunky continue resumes paused or saved generation.
chunky cancel permanently cancels generation. Your progress is discarded, but chunks that have already been generated are kept.

Info

By default, Chunky doesn’t resume automatically when your server restarts. During a normal shutdown, your progress is saved, and you can resume it afterward with chunky continue. To have Chunky automatically resume after every restart, set the continue-on-restart option to true in the Chunky configuration and reload it with chunky reload.

Tips for fast and stable generation

Generate when nobody is playing: Pregenerate the world before your players join, for example overnight. It’s faster and won’t disrupt anyone’s gameplay.
Keep the server from pausing: Newer Minecraft versions pause the server when no one is online. If this happens, go to the Configuration tab, set pause-when-empty-seconds to -1 in server.properties, and Chunky will keep running when there are no players online.
Set the world border appropriately: If the world border (/worldborder) or max-world-size in server.properties is smaller than the area you generated, mobs won’t spawn outside the border.
Pause map plugins: Plugins or mods such as Dynmap or BlueMap render every new chunk during generation. Pause rendering beforehand and resume it afterward.
Make sure you have enough RAM: During pregeneration, chunks are constantly loaded and unloaded. Chunky recommends at least 4 GB of RAM. If you don’t have enough memory, you can upgrade your server using Adjust Server under Actions.

Warning

Keep an eye on the load: A large generation process puts your server under heavy load for a long time. If your server’s resource limit is exceeded for an extended period, the server may be temporarily suspended. Generate in manageable steps and monitor the usage. Find out more in our guide to the Resource Limit.

Command overview

Control generation

Command	Description
`chunky start`	Starts generation for the current selection
`chunky pause`	Pauses ongoing generation and saves your progress
`chunky continue`	Resumes ongoing or saved generation
`chunky cancel`	Cancels generation and discards your progress

Set the selection

Command	Description
`chunky world [Welt]`	Selects the world to generate
`chunky shape [Form]`	Sets the shape, e.g. `square` (default), `circle`, `rectangle`, or `ellipse`
`chunky center [x] [z]`	Sets the center; if omitted, your current position is used
`chunky radius [Radius]`	Sets the radius in blocks, e.g. `5000`, `10k`, or `625c`
`chunky spawn`	Sets the center to the world spawn point
`chunky worldborder`	Uses the center and radius of the world border
`chunky corners [x1] [z1] [x2] [z2]`	Defines the selection using two corner points
`chunky pattern [Muster]`	Sets the generation order; the default is usually fine
`chunky selection`	Shows the current selection

Other commands

Command	Description
`chunky progress`	Shows the progress of all generation processes in-game
`chunky silent`	Turns progress messages off or on again
`chunky quiet [Sekunden]`	Sets how often progress messages appear
`chunky reload`	Reloads the Chunky configuration
`chunky trim`	Deletes chunks outside the selection

Warning

chunky trim permanently deletes chunks, including everything built in them. Make sure to create a backup in the Backups tab first, and restart the server after trimming.

Conclusion

Congratulations, you’ve installed Chunky and pregenerated your Minecraft world. Your players can now explore new areas much more smoothly. If you have any other questions or need help, our support team is available every day! 🙂

FAQ

Frequently asked questions

Install the Chunky plugin or mod on a server type such as Paper, Spigot, Fabric, Forge, or NeoForge. In the console, set the area with chunky center 0 0 and chunky radius 5000, then start generation with chunky start.

No. Chunky requires a server type that loads plugins or mods. Switch to Paper (plugin), or Fabric, Forge, or NeoForge (mod), under Games & Variants.

Yes. Use chunky pause to pause generation and save your progress, then chunky continue to resume. chunky cancel permanently stops generation, but keeps any chunks already generated.

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Minecraft: Pregenerate Your World (Chunks) with Chunky

Introduction

Before you start

Install Chunky

As a plugin (Paper, Spigot, Purpur)

As a mod (Fabric, Forge, NeoForge)

Check the installation

Pregenerate your world

Set the area and start

Pregenerate the Nether and End

Check progress, pause, and cancel

Tips for fast and stable generation

Command overview

Control generation

Set the selection

Other commands

Conclusion

Frequently asked questions

Minecraft

Install Chunky

As a plugin (Paper, Spigot, Purpur)

As a mod (Fabric, Forge, NeoForge)

Check the installation

Pregenerate your world

Set the area and start

Pregenerate the Nether and End

Check progress, pause, and cancel

Tips for fast and stable generation

Conclusion

Game Server

Servers & Hosting

ZAPX

Resources

ZAP-Hosting