Free Online Binary Tool

CRC Generator Online

Generate cyclic redundancy check values for text, hexadecimal bytes, or binary data. Choose a CRC variant and view the result in hexadecimal and binary, with an illustrative data-plus-CRC codeword.

Generate a CRC Code

All calculations run in your browser. Nothing is submitted to the server.

Text is encoded as UTF-8 bytes before the CRC is calculated.

Width: 8 bits. Polynomial: 0x07.

What Is a CRC Generator?

A cyclic redundancy check (CRC) is an error-detection method used in communication protocols, storage systems, embedded devices, and file formats. A CRC algorithm processes data using a polynomial-based calculation and produces a fixed-width value.

CRC-8

CRC-8 produces an 8-bit value. It can be useful in small messages and simple embedded communication systems.

CRC-16

CRC-16 produces a 16-bit value. Different variants, such as ARC, MODBUS, and CCITT-FALSE, use different parameters and are not interchangeable.

CRC-32 and CRC-32C

CRC-32 produces a 32-bit value and is commonly associated with formats such as ZIP and PNG. CRC-32C uses the Castagnoli polynomial and is used in systems including storage and network technologies.

Important: A CRC detects many accidental data changes, but it is not a cryptographic hash, authentication code, or encryption method. Use the exact CRC variant and protocol-specific byte order required by your system.

Supported CRC Variants

The following presets use standard parameter sets. The check value is the expected CRC for the ASCII text 123456789.

Variant Polynomial Initial value Check value
CRC-8 0x07 0x00 0xF4
CRC-16/ARC 0x8005 0x0000 0xBB3D
CRC-16/MODBUS 0x8005 0xFFFF 0x4B37
CRC-16/CCITT-FALSE 0x1021 0xFFFF 0x29B1
CRC-32/ISO-HDLC 0x04C11DB7 0xFFFFFFFF 0xCBF43926
CRC-32C 0x1EDC6F41 0xFFFFFFFF 0xE3069283

Frequently Asked Questions

What does CRC stand for?

CRC stands for cyclic redundancy check. It is a mathematical method for detecting accidental changes in data.

What is the difference between CRC-16 and CRC-32?

CRC-16 produces a 16-bit value, while CRC-32 produces a 32-bit value. Their variants use different parameters and provide different error-detection properties.

Why do CRC calculators sometimes give different answers?

They may use different polynomials, initial values, input or output reflection settings, final XOR values, or byte-order conventions.

Can I calculate a CRC from hexadecimal bytes?

Yes. Select hexadecimal input and enter complete bytes such as 31 32 33 34 35 36 37 38 39.

Is CRC secure for passwords?

No. CRC is intended for error detection, not password storage or cryptographic security.