CRC Calculator

Generic parameter model (poly / init / reflect / xor-out) with presets: CRC-8/16/32, CCITT, Modbus, CAN.

Input

Feed in text or HEX, then pick a preset or set poly / init / refin / refout / xorout yourself. In HEX mode, pasting a whole frame also checks its trailing CRC.

Data

CRC algorithm

Whole-frame check

Once enabled, the trailing bytes are read as the frame's CRC; feeding in plain data will report a mismatch, which is expected.

Result

6 bytes of data

CRC value

0xCDC5

Decimal

52677

Bytes (big endian)

CD C5

Bytes (little endian)

C5 CD

Notes

The CRC algorithms come from js-crc, whose model catalogue is generated from the reveng CRC catalogue; this tool only picks models, formats results and verifies whole frames.

Every preset is unit-tested against its official check value (the CRC of ASCII “123456789”), so a wrong model fails loudly.

Handy trick: for frames that append their CRC (Modbus RTU and friends), running the CRC over the whole frame should give 0x0000.

Everything is computed locally in your browser — nothing is uploaded.