Input Optimizer
by Kemmlow
Input Optimizer is a Fabric mod that runs on the client alone and narrows the gap between a physical mouse or keyboard action and the moment the game picks it up.
What it does
The mod corrects the point at which the game reads input. Vanilla Minecraft reads mouse and keyboard data later in each frame than necessary; this mod reads it earlier, so the render cycle receives newer values.
Support is split by platform. On Windows, Linux and macOS, the mod ships with the complete collection of lower-level OS input interface upgrades already active. Because the mod is client-side only, servers need nothing installed and it does not change server-visible behavior.
Key features
Near-zero input latency
Keyboard and mouse input reaches the game with minimal delay, closing the gap between a physical action and the game acting on it.
Direct OS input reads
Input is read straight from the operating system, skipping the standard GLFW layer rather than going through it.
Vanilla smoothing untouched
The vanilla mouse smoothing algorithm is left intact, and the mod does not change sensitivity or combat mechanics.
Automatic operation
The mod works as soon as the game launches, with no configuration or setup needed.
Gallery
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Use cases
Timing-sensitive play
Players who care about input responsiveness in PvP, building or speedrunning can use the mod without altering how the game plays.
Who it’s for: Players on Fabric who want lower input delay on Windows, Linux or macOS. The mod is for the client only, so server owners do not need to install it.
How it compares
Raw Input Buffer is a client-side Fabric mod released under the MIT License, covering 1.21 – 26.3. Projectile Optimizer is also client-side on Fabric and open source under the MIT License, but it covers 1.21.4 – 1.21.11 only. Input Optimizer covers 1.21.11 – 26.2 and is open source under the LGPL v3.0 only.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| Input Optimizer | Fabric | 1.21.11 – 26.2 | Client-side only | 2026-08-20 |
| Raw Input Buffer | Fabric | 1.21 – 26.3 | Client-side only | 2026-10-14 |
| Projectile Optimizer | Fabric | 1.21.4 – 1.21.11 | Client-side only | 2026-05-21 |
Questions
Does Input Optimizer need a server install?
Which platforms get full support?
Does Input Optimizer change mouse smoothing?
In the catalog
Input Optimizer is one of 3,545 Optimization mods on ModsFinder, and one of 2,575 Optimization mods for Fabric. 13,894 mods support Minecraft 26.2.
Similar mods
What the author says
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. 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…
Official listing
- Modrinth page
- modrinth.com/mod/inputoptimizer
- Owner
- Kemmlow
- Published
- 2026-04-17
- Updated on Modrinth
- 2026-08-20
- Facts verified
- 2026-10-15