What is a .MPK file?
MPK holds data in the compact binary MessagePack format, which has no official extension of its own. The same extension is also used for Nintendo 64 Controller Pak save dumps.
- Did you know
- MPK is the binary, space-saving cousin of JSON.
- MessagePack uses a type-length-value scheme where the first byte names the data type and can even hold small integers outright.
- It supports the same building blocks as JSON - maps, arrays, strings, numbers, booleans and null - plus a native binary type.
- What Analyser reads
- Identify and read developer and data-serialisation files: dependency lockfiles (npm/Yarn/pnpm/Cargo/Poetry/Bundler/Composer - locked-package count), binary serialisations (MessagePack, CBOR, BSON, raw Protobuf messages and descriptor sets), Python pickles with a security note, NumPy .npz and Java jar/war/ear archives, IDL schemas (FlatBuffers/Thrift/Cap n Proto/HCL), MATLAB MAT-files, Redis RDB dumps and columnar big-data containers (Apache Arrow/Feather, Parquet, ORC). The JSON supersets JSON5/JSONC/Hjson now open in a full viewer - see Notebooks & data above.
- Depth of analysis
- .MPK is an identification-grade format: Analyser recognises it from its bytes and decodes the header metadata it carries, rather than opening it in a full viewer. Formats that do get a full viewer are marked "Full" on the formats page.
- Open a .MPK file
- Drag a .MPK file onto the Analyser home page (or tap to pick one). It is identified entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.