ATLauncher vs Onyx Launcher

ATLauncher is a Minecraft launcher for browsing, downloading and installing modpacks. Its catalog includes packs from ATLauncher, CurseForge, Modrinth and Technic, and it supports multiple mod loaders and pack imports. Users can maintain separate instances so a new installation does not affect an existing one; the launcher automatically selects the Java version for a pack.

The launcher supports multiple accounts, including Mojang and Microsoft accounts and Xbox Game Pass subscribers. Instance management can install mods, maps and resource packs from CurseForge and Modrinth. It also offers one-click save backups and tools to create and run servers for ATLauncher modpacks. ATLauncher is free and has downloads for Windows, macOS and Linux, as well as a Jar download. Playing modpacks requires a purchased Minecraft account. The site no longer accepts submissions for its own pack platform and recommends Modrinth or CurseForge for sharing packs. For help, users can turn to Discord; contact form requests needing a response are answered within 24 hours.

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.