CRC Calculator Tool
Input
Tip: In auto mode, spaces, commas, and 0x prefixes are accepted.
Compute CRC for HEX bytes or UTF-8 text using preset algorithms.
Supports CRC-8, CRC-16/IBM, CRC-16/CCITT-FALSE,
CRC-32, and CRC-32C.
Tip: In auto mode, spaces, commas, and 0x prefixes are accepted.
CRC compatibility depends on width, polynomial, init, refin, refout, and xorout. If one parameter differs, checksums can differ even for identical input bytes.
Pick the algorithm specified by your protocol or device documentation.
Use HEX bytes or plain text (UTF-8). Auto mode handles common HEX notations.
Use CRC hex directly or the BE/LE byte order required by your packet format.
Common causes are parameter mismatch (poly/init/refin/refout/xorout), input parsing differences, and byte-order handling in transmitted packets.
Use whichever your protocol defines. Many modern systems use CRC-32C, while legacy protocols often require CRC-32 (ISO-HDLC).
Modbus RTU Frame Decoder · Modbus Function Codes · Modbus RTU Timing · Checksum Calculator · HEX ⇄ ASCII ⇄ Binary