a b s t r a c tThermogravimetric analyzer (TGA) is an analytical technique extensively used to study the thermal decomposition of inorganic solids, their kinetics, reaction mechanisms, chemical property, structure of intermediate and final products and synthetic conditions. This paper reports the development of microcontroller based thermogravimetric analyzer. The TGA has been setup with additional features like controlled gas delivery system suitable for the study of decomposition (gas-solid interaction) in various atmospheres like air, oxygen, hydrogen, etc. The displacement of the spring in the system due to sample weight loss or gain on heating can be measured by using Infrared (IR) grating assembly and also by using cathetometer (least count is 0.001 cm).