CRC Calculator

General CRC calculator

This calculator supports predefined cyclic redundancy check models from CRC-3 through CRC-82. The main choices include CRC-7/MMC, CRC-8/SMBUS, CRC-10/ATM, CRC-11/FLEXRAY, CRC-15/CAN, CRC-16/ARC, CRC-24/OPENPGP, CRC-32/ISO-HDLC, and CRC-64/ECMA-182. It also supports custom width, polynomial, initial value, reflection, and final XOR parameters.

CRC model names matter: two algorithms with the same checksum width can produce different results for the same input. Select the model required by your file format, protocol, device, or existing implementation.

Choose a focused calculator

• Use the CRC-16 calculator for CRC-16 models such as CRC-16/ARC, MODBUS, KERMIT, USB, XMODEM, and X-25. It defaults to CRC-16/ARC and returns a 16-bit result.
• Use the CRC-32 calculator for CRC-32 models such as CRC-32/ISO-HDLC, CRC-32C, POSIX cksum, BZIP2, and MPEG-2. It defaults to CRC-32/ISO-HDLC and returns a 32-bit result.
• Stay on this general calculator for other widths or when you need custom CRC parameters.

Using a custom CRC model

Select Custom, then enter the width, polynomial, initial value, final XOR value, and input/output reflection settings from your specification. To verify the setup, compare the result for a published check input such as ASCII 123456789 before calculating production data.

CRC checksums detect accidental changes, but they are not cryptographic hashes and do not protect data against deliberate modification.