---
id: crc32c
version: "2.8"
license: LGPL-2.1-or-later
license_treatment: copyleft
maintenance: active
---

# crc32c — A python package implementing the crc32c algorithm in hardware and software

License: copyleft · Maintenance: active · Popularity: top 1,000 on PyPI

## Install

pip install crc32c
uv add crc32c
poetry add crc32c

## Description

crc32c
======

.. image:: https://github.com/ICRAR/crc32c/workflows/Build%20and%20release%20to%20PyPI/badge.svg?branch=master

.. image:: https://badge.fury.io/py/crc32c.svg
    :target: https://badge.fury.io/py/crc32c

This package implements the crc32c checksum algorithm.
It automatically chooses between a hardware-based implementation
(using the CRC32C SSE 4.2 instruction of Intel CPUs,
and the crc32* instructions on ARMv8 CPUs),
or a software-based one when no hardware support can be found.

Because ``crc32c`` is in PyPI, you can install it with::

 pip install crc32c

Supported platforms are Linux and OSX using the gcc and clang compilers,
and Windows using the Visual Studio compiler. Other compilers in
Windows (MinGW for instance) might work.
Binary wheels are also provided in PyPI for major platforms/architectures.

The project is using certain gcc/clang compiler extensions to support
building hardware-specific functions that might not be supported
by older compiler versions.


Usage
-----

API
^^^

The core function exposed by this module is ``crc32c(data, value=0, gil_release_mode=-1)``.
It computes the CRC32C checksum of ``data``
starting with an initial ``value``...

## AI interpretation — verify before relying

Computes CRC32C checksums using hardware acceleration (SSE 4.2 on Intel, ARMv8 on ARM) when available, falling back to a software implementation otherwise.

Verdict: A well-maintained, actively developed package for fast CRC32C computation with transparent hardware acceleration. No known vulnerabilities, broad Python version support (3.7–3.14), and wide platform coverage via pre-built wheels. LGPL-2.1-or-later copyleft license requires careful review if bundling or modifying; suitable for data integrity checks in systems where hardware acceleration matters.

[View on SkillFed](https://skillfed.io/packages/crc32c) · [View on PyPI](https://pypi.org/project/crc32c/)