Checksum Calculator

CRC16 & Checksum

Input

Enter any text — each character's ASCII value is used

What is Checksum Calculator?

Calculate CRC16 (MODBUS, CCITT, IBM) and 8/16-bit checksum for ASCII text or HEX bytes. Used for serial communication, protocol verification.

How to Use

  1. Open the tool — Navigate to Checksum Calculator on tool.tl.
  2. Enter your data — Provide the input data or upload your file.
  3. Get results — Click the action button and get your results instantly.

Frequently Asked Questions

Is Checksum Calculator free to use?

Yes, Checksum Calculator is completely free with no registration required.

Is my data safe with Checksum Calculator?

Yes. Most processing happens in your browser. Files uploaded for conversion are processed server-side and automatically deleted.

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