CRC Calculator

CRC-8/16/32 with configurable poly, init, refin/refout and xorout, computed live from text or hex bytes.

Loads width/poly/init/refin/refout/xorout.
Hex mode accepts "01 A2 FF" / "01a2ff" / "0x01,0xA2".

How it works

This is a generic bit-by-bit CRC engine (the same model used by the Rocksoft/CRC RevEng catalogue): each input byte is XORed into the top of the shift register, optionally bit-reflected first, then shifted through width rounds, XORing in the polynomial whenever the top bit is set. The result is optionally bit-reflected and XORed with xorout. Presets are verified against the standard "123456789" check values. The Python / C / Rust snippets above implement the exact same algorithm for the current parameters and input, so you can copy-paste a working checksum function directly into firmware or scripts.