Modscraper Modscraper Minecraft
Lithium (Fabric/NeoForge) logo

Lithium (Fabric/NeoForge)

Mod

by JellySquid

An optimization mod for Minecraft which improves server performance significantly.

Type

Mod

CurseForge Downloads

95,102,143

CurseForge ID

360438

Modrinth Downloads

126,050,826

Modrinth ID

gvQqBUqZ

Last Updated

Sep 11, 2026

Description

Want to help support development?

Lithium is made possible thanks to the awesome supporters. Each pledge allows us to spend more time working on mods like these while helping to cover a few expenses.

Patreon 2No2Name Donation Link

And special thanks to everyone else who helped with the development of Lithium. If you're a programmer who would like to contribute to the project, consider taking a look at our open issues for ideas on how you can help.

You can join our discord community with support and discussion channels:

yHlVxSj.png

 

Lithium (for Fabric Loader)

Code license

Lithium is a general-purpose optimization mod for Minecraft, which works to improve a number of systems (game physics, mob AI, block ticking, etc) without changing any behavior. It works on both the client and server, and can be installed on servers without requiring clients to also have the mod. With the mod installed, you can expect to see more than a 50% improvement to tick times, resulting in a much faster game.

Even in single-player, your game runs an "integrated server" which ticks the world your player is in. Through optimizing the "server side" of the game, this can free up your computer's processor to focus on other tasks (i.e. rendering), resulting in improved frame rates and responsiveness. For multiplayer servers, administrators can expect a sizeable improvement to tick times, allowing their hardware to support more loaded entities, chunks, and players.

If you aren't using it already as well, Phosphor and Sodium both pair great with Lithium and are fully compatible.

Installation

Make sure you have the latest version of Fabric Loader present and then simply drop the mod into your mods folder. No other mods or additional setup (not even Fabric API!) is required.

You do not need to create new worlds in order to take advantage of the mod.

Features

You might be curious by now as to what exactly Lithium is doing in order to achieve such significant gains, and I'm happy you are! You can read about (some) of the changes we make in the spoiler below.

Physics optimizations: Entity collision detection has seen significant improvements through reducing the collision resolution complexity for simple, cuboid blocks. A more accurate algorithm is also used to reduce the number of blocks being checked every tick, especially in cases where entities are moving very quickly.

Mob AI optimizations: We make use of an event-based system for some tasks in order to reduce the CPU usage incurred by constantly polling the world for changes. Mob "brains" have also been optimized to select between different AI tasks much, much quicker than before. Comparison before and after here.

World generation optimizations: Many calculations in vanilla's world generation are unnecessary and do not affect the final result, which gives ample opportunity for Lithium to optimize this overhead away.

Chunk loading optimizations: The temporary data structures used in block palette compaction have been changed to be much more efficient. This results in fewer TPS drops while players are exploring terrain and provides a modest boost to world load times. We also batch some verification operations to reduce unnecessary disk I/O.

Mob farm optimizations: Mob cramming is significantly less expensive as resolving collisions between entities has been optimized to take advantage of the fact that simple boxes are involved. This makes mob farms considerably less harmful for server tick rates.

Block ticking optimizations: has less overhead, making things such as block update settling after generating chunks and other Redstone contraptions faster. This also reduces the amount of time it takes for a block to determine if it is ticking by schedule from O(n), where n is the number of ticking blocks, to O(1), providing a significant speedup when many blocks are being ticked.

Explosion optimizations: Many optimizations have been applied to TNT and explosions alike, reducing their associated lag without changing how they behave. In particular, ray-tracing is optimized to take advantage of the fact that multiple steps through a way will occur in the same block position, allowing us to quickly re-use the previous step's results. We also make use of a faster position tracking algorithm which avoids many excessive allocations.

Point of Interest optimizations: Complex mob AIs in Minecraft, primarily those belonging to Villagers and Pillagers, often need to find relevant points of interest in the world in order to choose the most appropriate AI task. In vanilla, querying all points within a chunk requires 16 separate retrievals through stream-heavy code. With Lithium present, this task is reduced to a single simple retrieval that makes use of a much faster (and traditional) iterator based approach, yielding anywhere from a 16-22x improvement for queries.

Data Tracker optimizations: The internal data manager used for tracking some entity state and properties has been optimized to use flat arrays and avoid expensive locking, providing a decent boost whenever these attributes are accessed during a game tick.

Redstone Wire optimizations: Calculating the new power level of redstone wire after a block update is costly. Reducing the number of blockstate checks without any change in behavior reduces redstone dust lag by about 35%.

... And other internal improvements to help the JVM better optimize code.

Configuration

Lithium makes use of an unusual configuration system which can be used to enable or disable certain patches. This system allows fine-grained control over what code is modified by Lithium, and as such, can be used to completely eliminate bugs or mod incompatibilities introduced by the mod. For more information, please read the wiki entry on modifying your configuration file. An empty configuration file is perfectly normal and just means you want to use the default options.

Modpack Permissions

This is a free and open-source project on CurseForge, and as such-- of course you can include it in your modpack! While not required, it's much appreciated if you link back to Lithium's project page and Patreon in your mods list or credits page.

Reporting Issues

Please use the issue tracker linked at the top of the page to report bugs, crashes, and other issues. The Curseforge comments section is not the place to report these kinds of problems and will likely result in you being asked to forward it along.

 

Recommended Gear

Affiliate

Hardware and extras that pair well with this mod.

As an Amazon Associate I earn from qualifying purchases.

Similar Mods

Included in Modpacks (3,240)

Show fewer
Re-Crafted 2 Re-Crafted 2 OpTimatic LITE Ultimate Client Ultimate Client Thoryx Thoryx AgoniaPack Lite AgoniaPack Lite Matched Matched Optimizium Optimizium CityKingFPS CityKingFPS Cyclo's Gearbound Cyclo's Gearbound Greveholm Essentials Greveholm Essentials Fantasism Fantasism Opium Cobblemon Opium Cobblemon DDAGCraft DDAGCraft MacOS Ready MacOS Ready Randomize Optimized Randomize Optimized Superior Performance Superior Performance Aeronautics: Complete Warfare Aeronautics: Complete Warfare UY8 Create+ UY8 Create+ The FPS: King Performance The FPS: King Performance Jurodedu Jurodedu SunsetCat's Create Modpack Vanilla Vibes Vanilla Vibes SIMPLY: Vanilla SIMPLY: Vanilla Nenuu's Legacy Pack Nenuu's Legacy Pack Amethyst Amethyst Storm Client Storm Client Quantum FPS Quantum FPS KnopiaPack KnopiaPack Surface Living Surface Living Iter Mutabilus: The Spread of Creation Iter Mutabilus: The Spread of Creation Glowy's Pack Glowy's Pack Crazily Optimized Crazily Optimized Suzeren Optimization Suzeren Optimization Steam Gardens SMP Steam Gardens SMP Weathered Weathered Create: FlyByWire Create: FlyByWire AgalarMC Vanilla AgalarMC Vanilla Cobble Champs Official Cobble Champs Official Sharkingo! Sharkingo! advanced graphics advanced graphics RE:mix RE:mix Create OneBlock | by Saurier.xyz Create OneBlock | by Saurier.xyz Create: War and Economy Create: War and Economy Advancement Race Modpack Advancement Race Modpack Better client Better client Solrise Solrise BeyondCraft BeyondCraft Bambam Modpack Bambam Modpack Ludari Create 1 Ludari Create 1 Create: Physics And Aeronautics [Server-Side] Create: Physics And Aeronautics [Server-Side] PI Craft PI Craft CobbleHelx Modpack (Cobblemon) CobbleHelx Modpack (Cobblemon) Simple Server Set: Base Simple Server Set: Base Performium Revived Performium Revived FPS - The Easy Way FPS - The Easy Way Mazite Mazite Renderium Optimized Renderium Optimized Electrical Warfare Electrical Warfare Create : Core Create : Core Lumora Lumora Holiday blocks Holiday blocks Create Horizons - Aeronautical Engineering Create Horizons - Aeronautical Engineering Vanilla Reimagined Vanilla Reimagined Bingotopia Bingotopia HoM -  Cobblemon World HoM - Cobblemon World Malficarum Malficarum Create - CMY Create - CMY OutBlocks: Simply Build OutBlocks: Simply Build Perfectly Perfected Perfectly Perfected Efficient Vulkan Efficient Vulkan SimplyCraft SimplyCraft Immersive Beauty Immersive Beauty BEBOU BEBOU VPatchcraft VPatchcraft IUT AIX IUT AIX Corpus 2026 Corpus 2026 Kryeit++ Kryeit++ CobbleSMP AX CobbleSMP AX Cute buff Cute buff Vanila+ by Sqeeze Vanila+ by Sqeeze ZuiderSchemer Pack ZuiderSchemer Pack [balls_game] [balls_game] Forever World Plus Forever World Plus FortPerf FortPerf TIMEGEAR TIMEGEAR SALOLAND SALOLAND Vanilla Elevated Vanilla Elevated LAHORI_PLAYZ LAHORI_PLAYZ Trial by Farmer Trial by Farmer New Worlds Geopol New Worlds Geopol Advance Optimization Advance Optimization MrOptimizer: Legend Edition MrOptimizer: Legend Edition Sachi's fps Client Sachi's fps Client Ron's Forever World Ron's Forever World [FMCS-S] fps X media X crystal x survival Optimized SERVER [FMCS-S] fps X media X crystal x survival Optimized SERVER Comfortable survival Comfortable survival Purely Optimized Purely Optimized Nolann's ModPack Nolann's ModPack FreshYoz FreshYoz Console Refined Console Refined

External Resources