FerriteCore

FerriteCore is a free Minecraft: Java Edition coremod focused on reducing RAM use by changing how the game stores block states, models, predicates, strings, voxel shapes, and baked quads. It supports Fabric, Forge, NeoForge, and Quilt and is listed for Minecraft versions 1.16.5 through 26.3, depending on loader builds. The project is marked for both client and server use, and its maintainer recommends installing it in both places because some optimizations apply on the server. Documented techniques include compacting block-state neighbor storage, caching multipart model predicates, and deduplicating model instances and baked quads. In cited examples, individual changes saved hundreds of megabytes, while one pack example showed post-garbage-collection memory falling from roughly 3.1 GB to 1.1–1.2 GB on the title screen. Several optimizations have no CPU impact during play, though some add load-time CPU cost. ThreadingDetector optimization is off by default due to a rare race-condition risk. The project uses the MIT license and links to GitHub for source code and issue reports.

FerriteCore targets memory use across several parts of Minecraft and supports both client and server environments. Check the loader-specific version compatibility and note that its ThreadingDetector optimization is off by default.

FerriteCore suits Minecraft: Java Edition players and server operators looking to reduce memory use. It is relevant to users of Fabric, Forge, NeoForge, or Quilt loader builds in its listed version range.

FerriteCore is a free, open-source coremod that reduces Minecraft: Java Edition memory use by changing how game data is stored and reused. It suits players and server operators running memory-heavy modpacks. Its focused memory optimizations make it a strong fit when RAM is the constraint, rather than a broad performance overhaul.

Overview

FerriteCore targets memory consumed by block states, models, predicates, strings, voxel shapes and baked quads. That narrow scope is useful: the documented savings can be substantial in some modded setups, while results will vary with the pack and configuration. Several optimizations have no CPU impact during play, though some add CPU cost at load time.

Key features

The biggest cited reduction comes from replacing per-state neighbor tables with FastMaps, saving around 600 MB in the documented test. Replacing blockstate property storage saves about 170 MB, and caching multipart model predicates saves 300–400 MB. These figures show where FerriteCore concentrates its work, not a guaranteed reduction for every pack.

Model-instance deduplication cuts roughly 200,000 multipart instances to about 1,500, saving close to 200 MB in the cited test. Quad deduplication saves close to 150 MB. The broader examples are striking: after garbage collection, memory in a Minecraft 1.16.4 Direwolf20 pack fell from roughly 3.1 GB to 1.1–1.2 GB on the title screen. In All Of Fabric 3 version 2.5.9, heap usage after world generation and a two-minute wait dropped from 1,792 MB to 984 MB. Treat these as results from particular configurations, not forecasts for your own installation.

ThreadingDetector changes are off by default because they may cause very rare race conditions. That conservative default favors stability, but users should not assume the optimization is active without changing it.

Pricing

FerriteCore is free: the open-source mod costs nothing under the MIT License. There is no paid tier or trial to weigh against its memory benefits.

Platforms

FerriteCore supports Minecraft: Java Edition and is available for Fabric, Forge, NeoForge and Quilt, with client-side and server-side support. Compatibility spans versions 1.16.5 through 26.3 depending on loader builds; check that the build matches both your loader and game version. It is not backported to versions earlier than 1.16.

The maintainer recommends installing it on both client and server because some high-impact optimizations apply server-side. FerriteCore does not require Sodium. On Fabric, builds for Minecraft 1.18 and newer are incompatible with Hydrogen, which is archived and has no releases for those versions. GitHub is the place to report issues and view the source.

Who it's for

Choose FerriteCore if a modded Minecraft installation is constrained by RAM and you want a focused, free optimization that can run on both client and server. It is less compelling if memory is not your bottleneck or if your exact game-and-loader combination lacks a compatible build. The cited reductions make it worth considering for memory-heavy packs, but they do not establish that every setup will save comparable amounts.

Pros and cons

• Pros: Targets several substantial sources of Minecraft memory overhead, with documented savings ranging from about 150 MB to around 600 MB for individual changes.
• Pros: Supports four mod loaders and both client and server environments, so its use is not limited to a single side of play.
• Pros: Free and MIT-licensed, with no trial or paid-plan decision.
• Cons: Savings depend on the tested pack and configuration; the headline examples are not promised results for other installations.
• Cons: Some changes carry load-time CPU cost, and ThreadingDetector remains disabled by default over rare race-condition risk.
• Cons: Loader-specific builds constrain compatibility, and newer Fabric builds conflict with Hydrogen.

Alternatives

For a broader comparison, see Minecraft Performance Mods. Lithium is another free Minecraft mod; consider it instead if you are looking beyond FerriteCore's memory-focused scope. Nvidium is free but requires Sodium and an NVIDIA GPU supporting mesh shaders, so it suits users who meet those hardware and dependency requirements. Exordium is a free client-side mod if your need is specifically client-side. ImmediatelyFast is a free, open-source client mod under LGPL-3.0-or-later for users seeking that kind of client-side option. Krypton is a free Minecraft mod under LGPL-3.0-only. VulkanMod is free and requires Fabric plus a GPU with Vulkan 1.2 support. Alternate Current is a free MIT-licensed Minecraft mod. ServerCore is a free option for self-hosted use.

Verdict

FerriteCore is the right choice for players and server operators who need to reduce Minecraft memory use and have a compatible loader build. Its strongest case is a set of targeted changes with substantial documented savings, at no cost. Look elsewhere if you need a broader performance tool, your setup is incompatible, or you expect the cited memory reductions to carry over unchanged to your pack.