Modbus RTU CRC-16 Checksum Calculator
Computes and verifies the 16-bit Modbus CRC for RTU serial frames.
Notice: engineering verification utility. Use test or de-identified data and verify results independently before relying on them.
How it works
Standard: Modbus over Serial Line Specification v1.02
Formula: Polynomial 0xA001, initial register 0xFFFF, bitwise shift check
Checks: Hex payload valid; CRC matches trailing two bytes little-endian
Calculated locally in browser memory; nothing leaves your browser.
Deterministic local-first client-side execution. Provided as-is without warranty.