KEPLER

Optimization-focused Minecraft client. In-game modules for 6 Minecraft versions from 1.20 to 26.3 with Fabric.

Get notified

Currently in private testing

Works on

Windows

Linux

macOS

Fabric

Forge

NeoForge

6 Minecraft versions

1.20.1, 1.21.1, 1.21.4, 1.21.8, 1.21.11, 26.3 builds

4 In-game modules

FPS/ping HUD, Keystrokes+CPS, Coordinates+direction, Zoom+Fullbright

Free

Open access

Supported platforms

Windows · macOS · Linux

Interface and Calibration

Experience the launcher interface and preview the live calibration between candidate profiles.

Kepler Client

Minecraft 1.21.x · Fabric Official sources

Hardware Calibration Click the button to start calibration

Profile A

Profile B

Profile C

Profile D

Sample display: not an actual benchmark.

Features Overview

Glowing cube and energy beam rising to the sky from a chest

ONE-CLICK START

OUT-OF-THE-BOX OPTIMIZED PROFILE

Ready-to-use optimized profile out of the box. JVM, memory (heap) settings, and mod selection are pre-configured for your hardware.

Fast-moving light trails and sunrise scenery

TAILORED TO YOUR HARDWARE

CALIBRATION FOR YOUR HARDWARE

In-launcher 2‑3 minute calibration tests 3-4 candidate profiles and selects the winning profile for your hardware.

Mod cubes and jigsaw pieces arranged in concentric rings in space

MODRINTH POWERED

EXTENSIVE MOD CATALOG

Mod catalog starting with Modrinth. Mod compatibility is checked for your game version directly via Modrinth.

Explore Further

All Details

Features

Full ready profiles, automatic Java selection, and in-game tools in development.

Compatibility

System

System requirement calculator, supported platforms, and mod loaders.

Plans

Roadmap

Private testing phase, expanded version support, and public release plans.

How it works

Choose your version Minecraft 1.21.x with Fabric

Run calibration 2‑3 minute test

Play Start with winning profile

Who it's for

Those seeking a profile tuned to their hardware

Calibration automatically selects the winning profile for your hardware.

Modded players

Mod compatibility is checked directly for your chosen game version via Modrinth.

Those who just want to play without setup hassle

The correct Java is selected automatically; you start with an out-of-the-box profile.

Kepler is currently in private testing. It will be open to everyone after testing.

Downloads are not yet available.

Get notified when we launch

Out-of-the-box optimized profile, automatic Java, extensive mod catalog. It will be here once tests conclude.

Stored data consists solely of email address and timestamp; used exclusively for launch announcements. Can be deleted upon request via the Discord or feedback page.

Free

Not affiliated with Mojang or Microsoft