Tested Devices

Modbus Master Simulator || Modbus Client Software || Modbus Scanner Software

Free Modbus Master simulator || Free Modbus Client || Free Modbus Scanner software

Are you looking for a software to test your slave devices on Modbus RTU or Modbus TCP? Well your search ends here.

The Radzio Modbus Master simulator is an excellent tool to simulate a Modbus Master and test slave devices. Moreover it is available completely free of cost. You can download your copy from here.

This software has been provided by Mr. Radoslaw Kwiecien.



-Supports Modbus RTU and Modbus TCP/IP

-Read Coil status (0xxxx), Input status (2xxxx), Input registers (3xxxx),  and holding registers (4xxxx)

- Data can be displayed as: Decimal, Integer, Hexadecimal, Binary, 32 bit float, 32 bit sw. float, 64 bit float,  64 bit sw. float

-Supports multiple connections

-Connection definitions can be saved for use in future

-Extremely easy to use with its intuitive interface

-Completely Free ! download and start using


-Download Radzio Modbus Master Simulator

-Download Tutorial- Radzio Modbus Master Simulator


Configuring and using it is extremely simple:

1) Start the Modbus master simulator


2)Click on the 'New File Icon'


3)This brings up the New file screen


4) Now click on Connection->Settings


5) This brings up the settings dialog box. You can select the protocol and set the communication parameters for the protocol using this dialog box.


6) After setting the parameters for communication click 'Connect' from the Connection menu


7) The Modbus master starts to poll the devices (as per the connection definition) on clicking connect. Now you can set the slave id and choose the register type you would like to query.