OptCraft

OptCraft

OptCraft provides ultimate control over your Minecraft performance!

by
1.3K Downloads
fabricgame-mechanicsoptimizationutility
Configure a Compatible Minecraft Server

About this Mod

OptiCraft Description

OptiCraft is a client-side Fabric performance mod focused on improving FPS stability, lowering stutter, and reducing unnecessary CPU/memory overhead in common gameplay scenarios.

It uses a modular optimization system so each performance feature can be toggled independently. You can run it in safe mode, tune individual modules, or enable aggressive presets for higher performance.

Core Focus Areas

  • Rendering: skips duplicate chunk rebuild scheduling where safe.
  • Client Tick: reduces repeated allocations in hot per-tick logic.
  • Entity Handling: caches repeated client entity lookups to reduce redundant work.
  • Memory: canonicalizes repeated Identifier objects with an LRU cache.
  • IO: uses async handling for non-critical tasks (like debounced config saves/resource sampling).
  • Networking: reduces packet-path allocations with identifier canonicalization.

Advanced Modes

  • Compatibility Mode: disables high/extreme risk patches for maximum mod compatibility.
  • Maximum Performance Mode: enables and tunes all major optimizations automatically.
  • Ultra Aggressive Mode: pushes cache and dedupe settings further.
  • Unsafe Extreme Mode: enables invasive FPS-first patches (particle budget limiting and short-window sound dedupe).

Configuration + UX

  • Full in-game config UI via Cloth Config (when installed).
  • Mod Menu integration for one-click config access.
  • Fallback config screen if Cloth Config is missing.
  • Built-in debug overlay with module state + optimization counters.

Compatibility

  • Fabric client mod.
  • Java 17+.
  • Universal best-effort jar targeting Minecraft 1.20.1+ with runtime-gated mixins.

Available Versions

OptCraft 1.0.0release
MC 1.20.1, 1.20.2, 1.20.3, 1.20.4, 1.20.5, 1.20.6, 1.21, 1.21.1, 1.21.2, 1.21.3, 1.21.4, 1.21.5, 1.21.6, 1.21.7, 1.21.8, 1.21.9, 1.21.10, 1.21.11fabric
March 3, 2026

How to Install OptCraft on Your Client

1

Install the Mod Loader Locally

Install fabric for your local Minecraft version.

2

Download the Matching File

Choose the OptCraft file for fabric and Minecraft 1.21.11.

3

Install Mod

Place the .jar file in your local .minecraft/mods folder and restart Minecraft. No server-side installation is required.

Compatibility

Mod Loaders

fabric

Minecraft Versions

1.21.11, 1.21.10, 1.21.9 (+15 more)

Server-side

Unsupported

Recommended RAM

4 GB(min. 3 GB)

Frequently Asked Questions

Does OptCraft need to be installed on the Minecraft server?

No. Modrinth marks OptCraft as unsupported on the server side. Install it only in your local Minecraft mods folder. Your server can remain unchanged unless the mod page lists an additional dependency.

Which version and loader does OptCraft require?

Use a file for fabric and your exact Minecraft version. Supported versions include 1.21.11, 1.21.10, 1.21.9. Files for different loaders are not interchangeable.

OptCraft is not working – what should I check?

First check the Minecraft version, loader version and required dependencies. Put the .jar file in your local .minecraft/mods folder and remove older duplicates. Because this mod is client-side, adding server RAM will not fix it.

Minecraft Server for Your Group

OptCraft stays on your client. Host a compatible world for your group.

Recommended RAM
4 GBfrom €5.2/mo
Minimum 3 GB | per 8 players
Create Server Now
Client Compatibility Guide
NVMe SSD Storage
DDoS Protection included

Details

License
LicenseRef-All-Rights-Reserved
Server-side
Unsupported

Supported Versions

1.21.111.21.101.21.91.21.81.21.71.21.61.21.51.21.41.21.31.21.2+8 more