Siegfried is a signature-based file format identification tool.

It implements:

  • the National Archives UK's PRONOM file format signatures
  •'s MIME-info file format signatures
  • the Library of Congress's FDD file format signatures (beta).


  1. download latest (v. 1.7.4) binary: (64bit | 32bit)
  2. copy to a location in your system path
  3. run the `sf -update` command to download the latest signatures (got troubles? Try this troubleshooting guide)

Mac Homebrew (or Linuxbrew)

brew install mistydemeo/digipres/siegfried

Or, for the most recent updates, you can install from this fork:

brew install richardlehane/digipres/siegfried

Ubuntu/Debian (64 bit)

wget -qO - | sudo apt-key add -
echo "deb wheezy main" | sudo tee -a /etc/apt/sources.list
sudo apt-get update && sudo apt-get install siegfried


pkg install siegfried

Identify a file

sf file.ext

Identify all files in a directory and its subdirectories

sf DIR

Identify all files in a directory but not subdirectories

sf -nr DIR

Use a redirect (">") to save your results

sf file.ext or DIR > my_results.yaml

Get identification results in CSV format (default is YAML)

sf -csv file.ext or DIR > my_results.csv

Get identification results in JSON format

sf -json file.ext or DIR > my_results.json

Scan within zip, tar, gzip, warc or arc files

sf -z file.ext or DIR

Calculate md5, sha1, sha256, sha512, or crc hash

sf -hash sha1 file.ext or DIR

Update your signature file

sf -update

Additional commands

For more detail on using sf, see this guide.

Modify your signature file

The roy tool builds siegfried signature files. For help using this tool, see this guide.

Detailed information about installing siegfried, identifying file formats, as well as more advanced topics, is available on the wiki.

Sets are a feature of the roy tool. They allow you to select groups of formats when building custom signatures. E.g. with a command like `roy build -limit @pdf`. These sets can be useful in other contexts, for example when defining a software workflow that only operates on certain types of files. You might, for example, want to isolate all the PUIDs for the formats that Apache Tika can text extract. Or the audio-visual files that Exiftool can generate metadata for. The sets tool allows you to do this online.

To view the source code and see the license details, go to the project page on Github. Please post any bugs or feature request to the issues page.

Join the Google Group for updates, signature releases, and help.

Try Siegfried

Richard's portrait

Drag a file on to Siegfried's anvil!