Calculate CRC32C Castagnoli checksums - the storage industry standard for SSDs and file systems.
About
CRC32C is a 32-bit cyclic redundancy check using the Castagnoli polynomial (0x1EDC6F41), optimized for detecting burst errors in storage systems with better error detection than standard CRC32.
Specifications
Output Size32 bits
StandardRFC 3720 (iSCSI CRC32C digest)
Standard Year2004
Origin Castagnoli CRC polynomial
Origin Year 1993
Use Cases
—SSD and NVMe storage integrity
—Google Protocol Buffers serialization
—Ext4 and Btrfs file systems
—iSCSI and SCTP network protocols
—Intel SSE4.2 hardware-accelerated checks
Security Notice
CRC32C is not cryptographically secure and must not be used for authentication or security purposes.
Frequently Asked Questions
CRC32C uses the Castagnoli polynomial (0x1EDC6F41) which provides better error detection for certain data patterns compared to the standard CRC32 (IEEE 802.3 polynomial). CRC32C is the standard for storage systems (SSD/NVMe) and Google Protocol Buffers.
Yes. Modern Intel and AMD CPUs support CRC32C acceleration via the SSE4.2 instruction set. This makes CRC32C extremely fast on modern hardware, often outperforming software-only implementations by 10x or more.
Use CRC32C when you need compatibility with storage systems, file systems (ext4, Btrfs), or network protocols that specify it. Use xxHash64 when you need higher speed and don't require protocol compatibility. CRC32C is for error detection, xxHash64 for general hashing.