VGSources / Best Minecraft Launchers / Onyx Launcher
What it is
Onyx Launcher is a free, MIT-licensed open-source desktop launcher for Minecraft on Windows and Linux. It manages separate instances and supports Vanilla, Fabric, NeoForge, Forge, and Quilt. Its built-in Modrinth catalog lets users browse, install, and update mods and modpacks, while modpack imports and automatic updates are supported. Onyx detects, downloads, and isolates Eclipse Temurin Java 8, 17, or 21 as needed. Diagnostic features measure FPS, average frame times, and stutters through a bundled Java agent; log analysis tracks memory and garbage-collection pauses, and Crash Bisect runs controlled launches to look for conflicting mods. World Guard makes safety snapshots before risky operations and supports rollbacks. Ghost Mode unloads the launcher window, WebContents, and GPU processes from memory when Minecraft starts. Microsoft sign-in uses OAuth Device Flow, and offline mode with custom skins is available. Windows builds are currently unsigned, so SmartScreen may warn; published SHA-256 checksums are provided.
Good, and not so good
- Free and MIT licensed
- Supports five Minecraft loaders
- Built-in Modrinth catalog
- Java versions managed automatically
- Crash and rollback tools included
- Windows builds are currently unsigned
- Requires checking SmartScreen warnings
- Limited to Windows and Linux
- Independent of Microsoft, Mojang, and Modrinth
Who it suits
Onyx suits Minecraft players managing multiple instances, mod loaders, and Modrinth content on Windows or Linux. Its diagnostics and rollback tools also fit users who troubleshoot modded installations.
Onyx brings instance management, mod discovery, Java setup, and troubleshooting into one desktop launcher. Users on Windows should account for unsigned builds and verify downloads with the published checksums.
Plans
- Free and open source100% Free & Open Source · MIT licensedFree
As lonestill.github.io lists them, read 8 Oct 2026.