MODBUS / ONLINE TOOL

Online Modbus Frame Parser

Decode RTU, TCP and raw register data. Paste a frame to inspect it.

Processed locally in your browser

01Input frame

HEX

Accepts spaces, commas, 0x prefixes or continuous hex. Read responses omit the start address: enter it from the request. Write frames use their embedded address.

02Parsed result

Ready to parse

Start with a frame

An example is ready above. Select Parse frame to inspect the CRC, register values and byte orders.

What can this Modbus decoder do?

Paste an RTU frame, TCP frame or raw register bytes. The parser checks RTU CRC, TCP MBAP lengths and supported PDU layouts, then displays the decoded values. It supports FC01–06, FC15, FC16 and exception responses.

How to use the frame parser

  1. Select RTU, TCP or raw register data and the request/response direction.
  2. Paste one complete hexadecimal frame. For a read response, enter the start address from the original request.
  3. Select Parse frame, inspect warnings and compare byte orders. Export CSV to retain values and annotations.

Frames are processed locally in your browser. This tool does not connect to a serial port or TCP device. Follow a worked RTU and TCP example or download the desktop app for live connections.

ModbusX · Online frame parserFC01–06 / FC15 / FC16 and exception responses