paq is a fast command-line utility for hashing individual files or complete directory trees. It uses the BLAKE3 cryptographic hash function and is designed to produce deterministic hashes from filesystem content, making it useful for checking integrity, detecting changes, comparing directory states, and incorporating content hashes into automated workflows.
Directories are processed recursively through a parallel pipeline. paq hashes discovered content, sorts the resulting hashes to keep output deterministic, and then hashes that ordered set to produce the final value. The tool deliberately concentrates on content rather than filesystem metadata, so ownership, permissions, timestamps, ACLs, extended attributes, and hard-link information do not contribute to the resulting hash. Symbolic links are handled by hashing their target paths rather than following and hashing the target contents.
paq can be used as a standalone executable or as a Rust crate. The command-line tool writes its result to a .paq file as valid JSON, while the crate exposes hashing functionality for Rust applications. Hidden files and directories can optionally be ignored.
This is free and open source software.
Key Features
- Hashes individual files or directory trees recursively with BLAKE3.
- Uses parallel processing to accelerate traversal and hashing.
- Produces deterministic results by sorting intermediate hashes before finalisation.
- Can optionally ignore hidden files and directories.
- Does not incorporate ownership, permissions, timestamps, ACLs, or extended attributes into content hashes.
- Hashes symbolic-link target paths without following the links.
- Provides both a command-line executable and reusable Rust crate.
- Writes command-line results to a .paq file using valid JSON.
Website: github.com/gregl83/paq
Support:
Developer: Gregory Langlais
License: MIT License
paq is written in Rust. Learn Rust with our recommended free books and free tutorials.
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| hashdeep | Generate and verify file hashes |
| hashit | Generate file hashes quickly |
Read our verdict in the software roundup.
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