Onyx Launcher vs Spectra Launcher

Onyx Launcher is a free, open-source desktop Minecraft launcher for Windows and Linux. It manages separate instances, imports modpacks and supports Fabric, NeoForge, Forge, Quilt and Vanilla. A built-in Modrinth catalog lets users browse, install and update mods and modpacks, while automatic updates and Java runtime management are included. Onyx can detect, download and isolate Eclipse Temurin Java 8, 17 or 21 as needed. Diagnostic features measure in-game FPS, average frame times and stutters, analyze logs, track memory and garbage-collection pauses, and use Crash Bisect to look for conflicting mods through controlled launches. World Guard creates 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; published SHA-256 checksums can be checked. The MIT-licensed project says it is independent of Microsoft, Mojang Studios and Modrinth.

Spectra Launcher is a free desktop launcher for starting Minecraft and keeping multiple installations separate. Each instance has its own Minecraft version, mods and worlds, and supports Vanilla, Fabric, Quilt, Forge and NeoForge. The launcher can browse and install mods, shaders, resource packs and modpacks from Modrinth and CurseForge, including their required dependencies. Players can sign in with Microsoft/Xbox or offline accounts; Spectra finds and installs the required Java version automatically. It also imports instances from Prism, CurseForge and the Modrinth app, and exports them as .mrpack or .zip files. Shared views collect worlds and screenshots, alongside 3D skin previews, saved skins and cape switching. Other tools include Quick Play for Minecraft 1.20+, server status with player counts and ping, live logs, crash-report sharing, optional Discord status and playtime tracking. Downloads are listed for Windows, macOS and Linux. Spectra says accounts, settings and instances stay on the user's computer, and Microsoft/Xbox passwords are not seen by the launcher.