Home/Tools/Modbus RTU CRC Checker

Modbus RTU CRC Checker

Calculate CRC-16 for Modbus RTU data bytes, or verify the CRC of a complete frame. See every step of the calculation.

Enter the data bytes you want to calculate CRC for — slave address, function code, and data. Do not include the CRC.

Examples

CRC-16/Modbus Quick Reference

ParameterValue
AlgorithmCRC-16/Modbus
Polynomial0x8005 (reflected: 0xA001)
Initial Value0xFFFF
Input ReflectionYes (LSB first)
Output ReflectionYes
Final XOR0x0000
Byte Order in FrameLittle-endian (low byte first)