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CRC

A pure Python library to calculate and verify CRC checksums.

Checks Coverage License Downloads Supported Python Versions PyPi Package Checks Coverage License Downloads Supported Python Versions PyPi Package

What it does

from crc import Calculator, Crc8

calculator = Calculator(Crc8.CCITT)

calculator.checksum(b"123456789")      # (1)!
calculator.verify(b"123456789", 0xF4)  # (2)!
  1. Returns the checksum as an int, here 0xF4.
  2. Returns True if the data matches the expected checksum.

Why use it

  • Python No dependencies

    Does not contribute to potentional dependency conflicts, easy to vendor if needed.

  • Batteries included

    More than 20 predefined configurations, plus support for custom configurations.

  • Portable

    As pure Python library with no native dependencies it runs wherever a python runs.

  • Flexible input

    Works with bytes, int, files, streams, iterables and anything convertible to bytes.

Where to go next

  • Getting started

    Install the library and calculate your first checksum.

    Getting started

  • Usage guide

    Task oriented guides for calculating, verifying and configuring CRCs.

    Usage guide

  • Configurations

    Browse every CRC configuration that ships with the library, including all of their parameters.

    Configurations

  • API reference

    Detailed documentation for the Calculator, Configuration and the low level register types.

    API reference

  • Command line

    Generate CRC lookup tables straight from your terminal with the bundled crc command.

    CLI

  • Development

    Set up a development environment and learn how to contribute.

    Development

References & resources