Format guide
What is an MRPack file?
An MRPack file is the Modrinth modpack format for Minecraft. It is a
ZIP-based archive that contains a modrinth.index.json manifest, Minecraft and
loader dependencies, file hashes, download URLs, and optional override files such as
configs or resource packs.
.mrpack file is a Minecraft Modrinth modpack
file. It is used by launchers to install a modpack from a manifest instead of storing every
mod file directly.
What is an MRPack file?
An MRPack file is a portable description of a Minecraft modpack. It tells a compatible launcher which Minecraft version to use, which mod loader is required, which files belong in the pack, and where remote mod files can be downloaded. This is why an MRPack file can be small even when the final installed modpack contains many JAR files.
What is inside an MRPack file?
The most important file is modrinth.index.json. This manifest describes the
pack name, format version, dependencies, and the files that should be present after the
pack is installed. Each file entry can include a path, hashes, environment flags, and one
or more download URLs.
- Minecraft version: the game version the pack expects.
- Loader dependency: Fabric, Forge, Quilt, NeoForge, or another loader.
- File list: paths, hashes, environment rules, and download URLs.
- Overrides: bundled files that should be copied into the instance root.
Why does MRPack use download URLs?
MRPack files are often compact because they do not always bundle every mod JAR. Instead, the manifest can point to approved remote files and let the launcher download them during import. This helps keep the pack small and makes it easier for a launcher to verify file hashes and choose the correct files for the target environment.
How do you open an MRPack file?
For normal play, import the original MRPack into a compatible launcher such as Modrinth App or Prism Launcher. If you only need to inspect the pack, use the MRPack Inspector. If you need a standard ZIP layout for a server panel, manual repair, or file transfer, use the MRPack to ZIP converter.
How do you get an MRPack file?
You usually get an MRPack file by downloading a Modrinth modpack or exporting a pack from a
launcher that supports the Modrinth format. If you only have a normal ZIP containing a
mods folder, that ZIP does not automatically become MRPack. A valid MRPack
needs the manifest fields, dependency data, file hashes, and download URLs that a launcher
can read.
How do you use an MRPack file in Minecraft?
Use a compatible launcher first. Import the .mrpack file into Modrinth App,
Prism Launcher, or another launcher that understands the format. The launcher reads
modrinth.index.json, downloads referenced mods, applies overrides, and creates
a playable Minecraft instance. If the launcher fails or you need a standard archive, then
inspect the file or convert MRPack to ZIP.
When should you convert MRPack to ZIP?
Convert MRPack to ZIP when the target workflow does not accept .mrpack
directly, when you need to inspect folders manually, or when browser-safe conversion can
show which referenced downloads are missing. Do not assume a converted ZIP is the same as a
launcher-native instance; it is a practical output format for inspection, repair, and
transfer.
Related guides
Compare the formats in MRPack vs ZIP, learn how to open an MRPack file, or follow the MRPack to ZIP conversion guide. If you want to extract the archive manually, read how to unzip an MRPack file.