
Modrinth · Minecraft mod
Input Optimizer
Near-zero client input latency.
Quick answer
Which Input Optimizer release should I use?
Input Optimizer 1.2.0-mc26.3 targets 26.3 with Fabric. It must be installed on the client. Do not install it on the dedicated server. No extra mods listed for this file.
Where it goes
Is Input Optimizer required on the client, server, or both?
It must be installed on the client. Do not install it on the dedicated server.
This file is marked client-only.
What else does Input Optimizer 1.2.0-mc26.3 need?
1.2.0-mc26.3. Change the file and its required mods may change too.
This file does not list any required mods. Do not add a library just because a different file uses it.
This file does not list any required or optional mods.
Before you install it
Add Input Optimizer without breaking your instance.
Built for Input Optimizer 1.2.0-mc26.3. Pick another file and the loader, install side or required mods may change.
- 01
Stick to this file
Use 1.2.0-mc26.3. It targets 26.3 with Fabric; another release may have different loader, side or dependency requirements.
- 02
Bring the mods it needs
This file does not list any required mods. Do not add a library just because a different file uses it.
- 03
Put it on the correct side
It must be installed on the client. Do not install it on the dedicated server.
- 04
Pick the file you checked
Use the “Get this file” button beside 1.2.0-mc26.3. It opens that exact file at the source.
About this project
What does Input Optimizer add?
Kemmlow's Input Optimizer

Kemmlow's Input Optimizer is a client-side Fabric mod that reduces the delay between your physical mouse and keyboard inputs and the game registering them.
What It Does

Minecraft processes mouse and keyboard input later in the frame cycle than it needs to. This mod corrects that by reading input earlier, feeding fresher data into the vanilla input pipeline, and aligning input consumption to the correct point in the render cycle.
On Windows, Linux, and macOS the mod bypasses the standard GLFW input layer and reads directly from OS level input APIs. This is the lowest level a mod can access without writing a device driver. The result is that input from your physical device reaches the game faster and through fewer intermediate layers.
Keyboard input timing is also improved on all platforms. This is not something comparable mods currently address.
The vanilla mouse smoothing algorithm is left completely intact. The mod changes nothing about how input feels.
What It Does Not Do
This mod does not affect rendering performance or framerate. It does not change mouse sensitivity, combat mechanics, or any data visible to servers. It does not remove or alter vanilla mouse smoothing. No configuration is needed or available. The mod works automatically on launch.
Why Download It
If input responsiveness matters to you in any context, whether that is PvP, building, speedrunning, or general play, this mod reduces the gap between your physical input and the game acting on it. It does this without changing any gameplay behavior and without requiring any setup.
Platform Support
Out of the box support is provided for Windows, Linux, and macOS, including the full set of lower level OS input API improvements. Partial support is provided for Android based Minecraft launchers, where limited input timing improvements apply. On any other platform the mod loads and falls back gracefully without causing issues.
Critical Information Before Downloading
This mod is client side only. Servers do not need to install it and will not detect any change. The mod does not affect any server visible behavior. Vanilla mouse smoothing is fully preserved.
Known Incompatibilities
FAQ
Is this client side only?
Yes. Servers do not need to install anything.
Does this increase FPS?
No. This mod does not touch rendering performance.
Does this change how the mouse feels?
No. Vanilla smoothing is completely preserved.
Does this affect servers or other players?
No. All changes are local to the client input path only.
Will it work on my system?
Out of the box support is provided for Windows, Linux, and macOS. Partial support is provided for Android based launchers. The mod falls back gracefully on any other platform.
License
LGPL-3.0-only
Copyright (c) Kemmlow
Project description from Modrinth.
Pick your setup
Input Optimizer by Minecraft version and loader
Choose the version and loader you play, then open the matching release.
26.2
1 loader build26.1.2
1 loader build26.1.1
1 loader build26.1
1 loader build1.21.11
1 loader buildCheck the dependencies, then try the file in a copied instance before changing a world you care about.
Recent files
Input Optimizer versions and loaders
1.2.0-mc26.3
inputoptimizer-1.2.0.jar
6 Nov 2026
1.2.0-mc26.2
inputoptimizer-1.2.0.jar
20 Aug 2026
1.1.0-mc1.21.11
inputoptimizer-1.1.0.jar
11 Aug 2026
1.1.0-mc26.2
inputoptimizer-1.1.0.jar
3 Aug 2026
1.0.0-mc26.2
inputoptimizer-1.0.0.jar
7 Jul 2026
1.0.0-mc26.1.1
inputoptimizer-1.0.0.jar
18 Apr 2026
1.0.0-mc26.1
inputoptimizer-1.0.0.jar
18 Apr 2026
1.0.0-mc1.21.11
inputoptimizer-1.0.0.jar
18 Apr 2026
1.0.0-mc26.1.2
inputoptimizer-1.0.0.jar
18 Apr 2026
Looking for an older file? The official Modrinth project page is in Resources.