No Unused Chunks

No Unused Chunks


A Minecraft mod that reduces world size by discarding unused chunks.

Client OptimizationUtility

Createda year ago
Updated3 months ago

NUC (fabric-1.19.3) - v2.0


  • Ported to fabric-1.19.4.
  • Did not port (aka removed) the "automatic chunk discarding" feature.
  • Did not port (aka removed) the "automatic chunk discarding config" feature.
  • Did port (aka kept) the feature for removing existing chunks from the "Optimize world" menu screen
  • This mod is now 100% client-side-only.

The reason the "automatic chunk discarding" was not kept is because I often saw it beeing seen as a "deoptimization" feature (which is true) that isn't worth sacrificing performance over, just to save some drive storage. In other words, trading server/single-player performance for storage space might not be worth it. Oh and, if you're wondering if it's possible to get this remaining feature to work on servers, well.. I'm not even gonna try, as it's not only too difficult for me to pull off, but it's also "unintended" behavor from the game's perspective (which ofc. can cause world corruptions and errors, so no, not doing that).

Important: Minecraft has one massive flaw. When "optimizing" worlds (and removing unused chunks), Minecraft loads the entire worlds into memory (RAM). If you have a huge world, and not enough RAM to fit it, then this could be a big problem for you. You could either try taking out dimension save files and optimizing them one by one, or you could use a tool like Thanos, Thanos-Shell (I made that one, scroll down on the webpage if needed), or another chunk removal tool or mod.


nounusedchunks-2.0+1.19.3.jar(46.96 KiB) Primary Download

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Technical information

Client side
Server side
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