Research on the drying processes of grain kernels in a thin layer requires data on moisture content changes inside kernels in selected time intervals of these processes. Before experimental tests to determine these changes are preformed, it is essential to assume the initial mass of grain samples. Deliberate determination of its value, taking into account the uncertainty of measuring instruments in the determination of sample mass in selected time intervals and sample dry mater content, provides results with a possibly low uncertainty. Unfortunately, despite the fact that the method for determining the initial mass of samples is generally available, quite often its value is not assumed deliberately. Therefore, the objective of this study was to develop software that could help in the determination of the initial mass of grain kernel samples dried in a thin layer. The paper also includes example results obtained with the use of the developed software, used for its validation.