checkdigit is a pure Python library built for identification numbers. You want to validate a credit card number, or maybe even calculate a missing digit on an ISBN code? We've got you covered 😎.

Want to know more? Check out the API Reference and documentation!

Installation

MacPorts 🍎

sudo port install py-checkdigit

PyPi 🐍

pip install checkdigit

✨ Features

• 📦 Works out of the box with all supported Python versions (3.7-3.11).
• ⌨️ PEP 561 compatible, with built in support for type checking.
• 🏃 Zero runtime dependencies. What you see is what you get.
• 🧮 Capable of calculating missing digits or validating a block of data.
• 📝 Extensive in-code comments and docstrings to explain how it works behind the scenes.

✅ Supported Formats

• Even/Odd binary parity
• CRC

• GS1 Standards

  • EAN-8/13
  • GDTI
  • GLN
  • SSCC
  • UPC-A/E
  • etc. (all fixed length numeric GS1 data structures with a check digit)

• ISBN-10/13
• Luhn
• Verhoeff

For each of these formats, we provide functions to validate them and calculate missing digits.

Do you have any formats that you'd like to see supported? 🤔 Feel free to raise an issue, or even to send a pull request!

✨ Contributors

This project follows the all-contributors specification. Contributions of any kind are welcome!

Want to help out? Check out the contributing page.

Thanks goes to these wonderful people (emoji key):

Timothy Langer ⚠️ 📖

Charlie Wilson 💻 ⚠️

Max Bowman 💻 ⚠️

Mohsen BANAN 🐛

📙 License

This project is licensed under GPL-3.0-or-later.