How to Pre-Generate Chunks on Your Minecraft Server with Chunky

Use the Chunky plugin to pre-generate Minecraft world chunks, eliminate exploration lag, and dramatically improve TPS for your players.

Chunk generation is the single most CPU-intensive operation on a Minecraft server. Every time a player walks into a new area, the server has to generate terrain, biomes, structures, ores, and decorations — and that work happens on the main thread, causing TPS drops and rubber-banding.

The fix is to pre-generate chunks before players need them. The Chunky plugin walks the world in advance and generates everything within a radius, so when players explore, the chunks already exist and load instantly.

Why it matters: A pre-generated server can comfortably handle 50+ players. A non-pre-generated server can lag at 10 players just from one player flying around in a new direction.

Install Chunky

Download Chunky

Get Chunky from Modrinth. It supports Paper, Spigot, Bukkit, Folia, Forge, NeoForge, and Fabric.

Server type	Download
Paper / Spigot / Bukkit	`Chunky-X.X.X.jar` → `plugins/`
Forge / NeoForge	Forge build → `mods/`
Fabric	Fabric build → `mods/` (also needs Fabric API)

Upload to your server

In the XGamingServer Panel, click Files. Navigate to plugins/ (or mods/), and upload the Chunky JAR.

Restart the server

Restart from Console. Verify Chunky loaded:

/chunky

You should see the Chunky help output.

Plan Your Pre-Generation

Before you start, decide:

Your final world border size — pre-generate to match
Which dimensions to pre-generate (Overworld, Nether, End)
The center — usually 0, 0 (spawn) but can be wherever your community is based

Match your world border. Pre-generating beyond your border is wasted work. Pre-generating less than your border means players will still hit ungenerated chunks.

Pre-Generate Chunks

Set the dimension (optional)

Default is the Overworld. To pre-generate the Nether or End instead:

/chunky world world_nether

Or:

/chunky world world_the_end

Set the center (optional)

Default center is 0, 0. To use a different point:

/chunky center 1000 -2000

Set the radius

The radius is in blocks from the center.

/chunky radius 5000

This will generate everything within a 10,000 × 10,000 block area centered on 0, 0.

Start generation

/chunky start

Chunky begins walking the world. The server will be laggy while this runs — chunk generation is CPU-intensive. Run when no players are online.

Check progress

/chunky status

Shows percent complete, current chunk, ETA, and chunks per second.

Pause / resume / cancel

/chunky pause
/chunky continue
/chunky cancel

Pause-and-continue works across restarts. Chunky saves progress to disk.

How Long It Takes

Radius	Total chunks	Approx. time on hosted server
1,000 blocks	~16,000	5–15 minutes
2,000 blocks	~64,000	20–40 minutes
3,000 blocks	~144,000	1–2 hours
5,000 blocks	~400,000	3–6 hours
10,000 blocks	~1.6M	12–24 hours
25,000 blocks	~10M	Several days

Times vary heavily based on:

Server CPU — single-thread performance dominates
Modded vs vanilla — modded chunk gen can be 5–10× slower
World type — amplified terrain takes longer than normal
Concurrent players — generation slows under load

Multi-Dimension Workflow

To pre-generate all three dimensions, run them sequentially:

/chunky world world
/chunky radius 5000
/chunky start

Wait for completion, then:

/chunky world world_nether
/chunky radius 1000
/chunky start

Then:

/chunky world world_the_end
/chunky radius 1500
/chunky start

Nether is 1:8 scale. Pre-generate the Nether to 1/8th of your Overworld radius — world 5000 → world_nether 625.

Set a World Border After Generation

Once pre-generation is complete, lock the world border so players can't venture beyond:

/worldborder set 10000

This sets a 10,000-block diameter border (5,000 blocks from center). Players will be blocked from going further, so they only ever experience pre-generated chunks. Zero exploration lag forever.

Tips

Run overnight — pre-generation tanks TPS. Start it before bed, check it in the morning
Lower view-distance during generation to free CPU for Chunky
Match your world border — don't generate more than you'll use
Pre-generate before opening to players — never on a busy live server
Check disk space — large pre-generations can use several GB
Re-run after biome changes — if you change a datapack, only newly-generated chunks reflect it
Use /chunky pause before risky restarts — Chunky resumes cleanly

Common Issues

Problem	Fix
Server unplayable while Chunky runs	Expected — run during off-hours. Lower view-distance and reduce Chunky speed
Chunky crashes the server on modded	Some Forge mods conflict with Chunky's chunk loader. Try smaller batches
`Out of memory` during generation	Increase server RAM, or reduce the radius. Modded gen needs more RAM
Chunky generates the wrong dimension	Use `/chunky world <name>` first
Old chunks aren't updated	Chunky only generates missing chunks — existing ones aren't changed
Generation appears stuck	Check `/chunky status` — modded biomes can take seconds per chunk

Faster Pre-Generation Alternatives

Option	Speed	Notes
Chunky (default speed)	Baseline	Stable, well-tested
Chunky with `/chunky pause-on-time`	Same	Auto-runs only during off-peak
Offline pre-generation tools	2–5× faster	Generate the world before uploading
Higher CPU server tier	2–3× faster	Single-thread perf matters most

Common Mistakes

Mistake	Fix
Pre-generating with players online	TPS will tank — kick players or run overnight
Setting a tiny radius "to test"	Test with at least `radius 500` to see realistic timing
Forgetting to set a world border after	Players will still generate chunks beyond your pre-gen
Pre-generating the Nether at the same radius as Overworld	Nether is 1:8 — use 1/8th the radius
Pre-generating then changing the seed	Wastes all the work — set seed first
Not pre-generating before a big launch	Day-1 lag will kill your community before it starts

How to Pre-Generate Chunks on Your Minecraft Server with Chunky

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