Chunky is a server-side utility mod that pre-generates chunks quickly and efficiently for Minecraft, available for Fabric, Forge, and NeoForge as well as Bukkit-based server platforms like Paper and Spigot.
Every Minecraft server owner knows the problem: a player runs into unexplored territory, the server scrambles to generate new chunks on the fly, and everyone on the server feels the lag spike. This is especially brutal during events, opening day, or when your world border is large. Chunky solves this by letting you pre-generate all the chunks within a defined area before players ever set foot there. With over 11 million downloads on Modrinth and active development since 2021, it has become one of the most trusted world-generation utilities in the Minecraft ecosystem. Created by pop4959 and released under the GPL-3.0 license, Chunky is free, open-source, and battle-tested on servers of all sizes.
Key Features of Chunky Mod
- Concurrent chunk generation tasks — Chunky lets you run multiple chunk generation tasks simultaneously, which means you can leverage more of your CPU to get the job done faster. If you have a beefy dedicated server sitting idle before launch day, you can spin up several tasks and pre-generate your entire world in a fraction of the time a single task would take.
- Pause and resume generation — You can pause any chunk generation task at any time, and Chunky saves your progress automatically. This is invaluable for server admins who need to bring a server online for scheduled play sessions but still have world generation in progress. Simply pause, let players enjoy lag-free gameplay, then resume later.
- Detailed progress tracking — Chunky provides real-time statistics including chunks processed, percentage to completion, estimated time remaining, and chunk processing rate. Instead of staring at a blank console wondering how long generation will take, you get clear, actionable data that helps you plan your server maintenance windows.
- Custom world shapes — Rather than being locked into a square generation area, Chunky supports multiple shapes including circles and custom geometries. This is particularly useful if your server uses a circular world border — you can match the generation shape to the border and avoid wasting time generating chunks that players will never reach.
- World border integration with ChunkyBorder — When paired with the companion plugin ChunkyBorder, Chunky can automatically detect and match your existing world border settings. One command reads your border configuration, and Chunky generates exactly the chunks within that boundary. No manual coordinate math required.
- Comprehensive command system — Chunky offers a full suite of commands for selecting worlds, setting centers and radii, choosing generation patterns, and trimming unused chunks. Commands like
chunky worldborderandchunky spawneliminate guesswork by pulling coordinates directly from your world settings, making the setup process fast even for less technical admins. - Chunk trimming — Beyond generation, Chunky can delete chunks outside your selected area with the
chunky trimcommand. This is a powerful tool for reducing world file size on servers that have been running for a long time, clearing out abandoned chunks that no one visits and freeing up disk space.
Screenshots
How to Install Chunky Mod
- Determine your server or client platform. Chunky supports Fabric, Forge, NeoForge, and server platforms like Paper and Spigot.
- Download the correct version of Chunky for your Minecraft version and mod loader from the download section below.
- Place the downloaded
.jarfile into your server'splugins/folder (for Bukkit/Paper/Spigot) ormods/folder (for Fabric, Forge, or NeoForge). - Restart your server or client. Chunky will load automatically and make its commands available.
- Verify the installation by running
chunky selectionin the server console or in-game chat. If Chunky responds with the current selection info, you are ready to start pre-generating.
Requirements & Compatibility
| Requirement | Details |
|---|---|
| Minecraft Versions | 1.16.5 – 1.21.11 |
| Mod Loaders | Fabric, Forge, NeoForge |
| Server Platforms | Bukkit, Spigot, Paper, Folia, Sponge |
| Permissions | Operator status on servers, or singleplayer with cheats enabled |
| Optional Companion | ChunkyBorder (for world border integration) |
| License | GPL-3.0-only (free and open-source) |
Pros and Cons
Pros
- Eliminates lag spikes from on-the-fly chunk generation
- Works across nearly every major server and client platform
- Supports concurrent tasks to maximize CPU usage
- Pause and resume lets you schedule generation around play sessions
- Detailed progress stats help plan maintenance windows
- Free, open-source, and actively maintained since 2021
Cons
- Requires operator permissions, which can be a barrier on shared hosting
- World border integration needs the separate ChunkyBorder plugin
- Pre-generation is CPU-intensive and may affect server performance while running
- Command-only interface with no GUI — less intuitive for new server admins
Alternatives to Chunky Mod
- Chunk Pregenerator — A long-standing pre-generation mod for Forge that offers a visual map interface and supports multiple dimensions, making it a solid choice for admins who prefer a GUI over commands.
- Noisium — Focuses on optimizing the world generation engine itself rather than pre-generating chunks, which can reduce lag spikes without requiring any upfront generation time.
- Lithium — A general-purpose server optimization mod that improves tick performance across the board, often used alongside Chunky to keep servers running smoothly after chunks are generated.
Download Chunky Mod
| Minecraft Version | Fabric | Forge | NeoForge |
|---|---|---|---|
| For Minecraft 1.21.11 | Download | Download | Download |
| For Minecraft 1.21.10 | Download | Download | Download |
| For Minecraft 1.21.9 | Download | Download | Download |
| For Minecraft 1.21.8 | Download | Download | Download |
| For Minecraft 1.21.7 | Download | Download | Download |
| For Minecraft 1.21.6 | Download | Download | Download |
| For Minecraft 1.21.5 | Download | Download | Download |
| For Minecraft 1.21.4 | Download | Download | Download |
| For Minecraft 1.21.3 | Download | Download | Download |
| For Minecraft 1.21.2 | Download | Download | Download |
| For Minecraft 1.21.1 | Download | Download | Download |
| For Minecraft 1.21 | Download | Download | Download |
Always download mods from official sources to stay safe.
Frequently Asked Questions
Does Chunky cause lag while it is pre-generating chunks?
Yes — pre-generation is inherently CPU-intensive, so you may notice some performance impact while tasks are running. However, Chunky is designed to be throttled, and you can pause generation at any time if players are online. Many server admins run Chunky during off-peak hours or before the server opens to the public to avoid any player-facing lag.
Can I use Chunky on a singleplayer world?
Yes, Chunky works in singleplayer worlds. On older Minecraft versions, you may need to enable cheats for the world first, either during world creation or by using the "Open to LAN" button in the pause menu. Once cheats are enabled, all Chunky commands become available.
Is Chunky compatible with Fabric and Forge at the same time?
No — you need to download the specific version that matches your mod loader. Chunky provides separate builds for Fabric, Forge, and NeoForge. Check the download table above and select the correct file for your platform to avoid compatibility issues.
Does Chunky work with custom world generators like Terralith?
Yes, Chunky works with custom world generators because it simply triggers the game's own chunk generation process. Whatever worldgen mod or datapack is active in your world will be used when Chunky generates chunks. This makes it compatible with popular worldgen mods without any special configuration.
How long does it take to pre-generate a 10,000 block radius world?
It depends on your hardware and world generator complexity. A typical dedicated server might process several hundred chunks per second, meaning a 10,000 block radius circle could take several hours. Chunky's built-in ETA display shows you exactly how long remains, and you can speed things up by running multiple concurrent tasks if your CPU has cores to spare.
