- Author: Brian Neal <bgneal@gmail.com>
- Version: 1.0.0
- Date: November 6, 2025
- Home Page: https://github.com/gremmie/m209
- License: MIT License (see LICENSE.txt)
- Documentation: https://m209.readthedocs.org
- Support: https://github.com/gremmie/m209/issues
The M-209 is a mechanical cipher machine used by the US military during World War II and up to the Korean War. The M-209 is also known as the CSP-1500 by the US Navy. The M-209 is an example of a Hagelin device, a family of mechanical cipher machines created by Swedish inventor Boris Hagelin.
This project is a Python 3 library and command-line utility for encrypting and decrypting text by simulating the operation of an actual M-209 device.
Please see the documentation for library usage, tutorials and references.