# Prism Launcher > Prism Launcher is an open-source Minecraft launcher for instances and modpacks. Prism Launcher is a free, open-source (GPL-3.0) Minecraft launcher for Windows, macOS and Linux. It manages multiple isolated instances, accounts, mods and modpacks, with Modrinth and CurseForge built in. A Minecraft account that owns the game is required. Not affiliated with Mojang or Microsoft. Canonical download: https://prismlauncher.ink/download Last reviewed: 2026-10-17 ## Docs - [Prism Launcher Instance Management](https://prismlauncher.ink/instances.md): Create, clone, group, export, and back up isolated Minecraft instances on Windows with independent mods, resource packs, and Java versions. - [Prism Launcher Modpacks & Mod Downloader](https://prismlauncher.ink/modpacks.md): Download and update modpacks from Modrinth, CurseForge, FTB, Technic, and ATLauncher directly inside Prism Launcher on Windows. - [Prism Launcher Mod Loaders](https://prismlauncher.ink/loaders.md): Install or switch Fabric, NeoForge, Forge, Quilt, or LiteLoader on any Minecraft instance in two clicks without manual JAR installers. - [Prism Launcher Java & JVM Configuration](https://prismlauncher.ink/java.md): Match the exact Java runtime (Java 21, Java 17, or Java 8) to your Minecraft version, tune min/max RAM, and pass GC JVM arguments. - [Prism Launcher Windows Setup & Installation](https://prismlauncher.ink/setup.md): Install Prism Launcher on Windows 10 and 11, choose between the MSVC installer and Portable ZIP, and add Microsoft or offline profiles. - [Prism Launcher How-To Tutorials](https://prismlauncher.ink/howto.md): Step-by-step fixes for Exit Code 1 and -1, installing Iris/Complementary shaders, importing MultiMC folders, and adding offline accounts. - [Prism Launcher vs Other Minecraft Launchers](https://prismlauncher.ink/compare.md): Side-by-side comparisons of Prism Launcher against the official Minecraft Launcher, CurseForge App, Modrinth App, MultiMC, ATLauncher, and Lunar. - [Prism Launcher Technical Glossary](https://prismlauncher.ink/words.md): Clear definitions of Minecraft modding and launcher terms: `.mrpack`, Fabric vs NeoForge, JVM heap flags, G1GC/ZGC, and Exit Code 1. - [Prism Launcher Frequently Asked Questions](https://prismlauncher.ink/ask.md): Answers to the most common questions about Prism Launcher safety, Microsoft OAuth login, offline mode requirements, and open-source GPLv3 status. - [Prism Launcher Technical Topics](https://prismlauncher.ink/topics.md): Advanced guides on pre-launch and post-exit scripts, shared screenshot symlinks, portable USB setups, and custom launcher themes. - [Prism Launcher Version & Loader Routes](https://prismlauncher.ink/routes.md): Complete setup blueprints pairing every major Minecraft version and mod loader with specific modding goals and Java requirements. ## Featured - [How to install Prism Launcher on Windows](https://prismlauncher.ink/howto/install-prism-launcher-on-windows.md): Install Prism Launcher on Windows: download the installer, run setup, sign in and create your first instance. - [Prism Launcher Instance Management](https://prismlauncher.ink/instances.md): Create, clone, group, export, and back up isolated Minecraft instances on Windows with independent mods, resource packs, and Java versions. - [Prism Launcher Modpacks & Mod Downloader](https://prismlauncher.ink/modpacks.md): Download and update modpacks from Modrinth, CurseForge, FTB, Technic, and ATLauncher directly inside Prism Launcher on Windows. - [Prism Launcher Mod Loaders](https://prismlauncher.ink/loaders.md): Install or switch Fabric, NeoForge, Forge, Quilt, or LiteLoader on any Minecraft instance in two clicks without manual JAR installers. - [Prism Launcher Java & JVM Configuration](https://prismlauncher.ink/java.md): Match the exact Java runtime (Java 21, Java 17, or Java 8) to your Minecraft version, tune min/max RAM, and pass GC JVM arguments. - [Prism Launcher Windows Setup & Installation](https://prismlauncher.ink/setup.md): Install Prism Launcher on Windows 10 and 11, choose between the MSVC installer and Portable ZIP, and add Microsoft or offline profiles. - [Prism Launcher How-To Tutorials](https://prismlauncher.ink/howto.md): Step-by-step fixes for Exit Code 1 and -1, installing Iris/Complementary shaders, importing MultiMC folders, and adding offline accounts. - [Prism Launcher vs Other Minecraft Launchers](https://prismlauncher.ink/compare.md): Side-by-side comparisons of Prism Launcher against the official Minecraft Launcher, CurseForge App, Modrinth App, MultiMC, ATLauncher, and Lunar. - [Prism Launcher Technical Glossary](https://prismlauncher.ink/words.md): Clear definitions of Minecraft modding and launcher terms: `.mrpack`, Fabric vs NeoForge, JVM heap flags, G1GC/ZGC, and Exit Code 1. - [Prism Launcher Frequently Asked Questions](https://prismlauncher.ink/ask.md): Answers to the most common questions about Prism Launcher safety, Microsoft OAuth login, offline mode requirements, and open-source GPLv3 status. - [Prism Launcher Technical Topics](https://prismlauncher.ink/topics.md): Advanced guides on pre-launch and post-exit scripts, shared screenshot symlinks, portable USB setups, and custom launcher themes. - [Prism Launcher Version & Loader Routes](https://prismlauncher.ink/routes.md): Complete setup blueprints pairing every major Minecraft version and mod loader with specific modding goals and Java requirements. - [Fabric Loader in Prism Launcher](https://prismlauncher.ink/loaders/fabric-loader.md): Lightweight, modular mod loader that updates within hours of new Minecraft releases and powers the modern Sodium/Iris performance stack. Supports Minecraft 1.14 – 1.21.4+ (plus snapshots). - [NeoForge in Prism Launcher](https://prismlauncher.ink/loaders/neoforge-loader.md): The modern community-driven successor to Minecraft Forge for 1.20.4 and 1.21+, supported natively in Prism Launcher's Version tab. Supports Minecraft 1.20.1 – 1.21.4+. - [Fabulously Optimized on Prism Launcher](https://prismlauncher.ink/modpacks/fabulously-optimized.md): Flagship Fabric performance and OptiFine-parity modpack offering massive FPS gains, shaders, connected textures, and controller support. Runs on Fabric (1.16.5 – 1.21.4) with 2 GB – 4 GB RAM and Java 21 (for 1.20.5+). - [All the Mods 10 (ATM10) & ATM9 on Prism Launcher](https://prismlauncher.ink/modpacks/all-the-mods-10-atm10.md): Kitchen-sink tech, magic, and exploration progression pack featuring 400+ mods and custom endgame ATM Star crafting. Runs on NeoForge (1.21.1) / Forge (1.20.1) with 8 GB – 10 GB (8192 MB) RAM and Java 21 (ATM10) / Java 17 (ATM9). - [Cobblemon Official Modpack on Prism Launcher](https://prismlauncher.ink/modpacks/cobblemon-modpack.md): Open-source creature-catching modpack blending seamlessly into vanilla Minecraft biomes with custom animations and competitive battles. Runs on Fabric or NeoForge (1.20.1 / 1.21.1) with 4 GB – 6 GB RAM and Java 17 or Java 21. - [Java 21 (64-Bit) for Minecraft 1.20.5 & 1.21+](https://prismlauncher.ink/java/java-21-temurin-minecraft-1-20-5-1-21.md): Mojang upgraded Minecraft 1.20.5 and 1.21+ to require a 64-bit Java 21 runtime; launching with Java 17 or Java 8 causes an immediate incompatible class version crash. Applies to Minecraft 1.20.5, 1.20.6, 1.21 – 1.21.4+. - [RAM Allocation (Minimum & Maximum Memory MiB)](https://prismlauncher.ink/java/ram-allocation-min-max-memory-slider.md): Setting Maximum Memory too low causes OutOfMemory freezes, while setting it above 10–12 GB can cause long garbage-collection lag spikes. Applies to All Minecraft versions. - [Prism Launcher vs Official Mojang / Microsoft Minecraft Launcher](https://prismlauncher.ink/compare/prism-launcher-vs-official-minecraft-launcher.md): Prism Launcher opens in under a second, isolates every modpack in its own folder, and downloads mods from Modrinth and CurseForge directly without the heavy Electron store shell. - [Prism Launcher vs CurseForge Standalone / Overwolf App](https://prismlauncher.ink/compare/prism-launcher-vs-curseforge-app.md): Prism Launcher is 100% ad-free, open-source, and installs both CurseForge and Modrinth modpacks in one lightweight app without bundling Overwolf. ## Optional - [Full catalog](https://prismlauncher.ink/llms-full.txt): every topic page in Markdown - [Sitemap](https://prismlauncher.ink/sitemap.xml)