Abstract This article focuses on the basic processing of gravity-magnetic data to separate fields into regional and local components. A key stage in the processing and interpretation of gravimetric and magnetic data is the potential field transformation phase, which involves identifying local and regional anomalies from the total observed field. Local potential field anomalies reflect structural heterogeneities in the density and magnetic properties of rocks, while regional anomalies are associated with the deep structure of the Earth's crust. To perform the transformation of gravimetric and magnetic fields, the department developed an algorithm and the Force-Fortran program IZOTR, which enables digital data transformation using various transformation methods. This article describes the algorithm and block-diagram of the IZOTR program, as well as some of the results of processing actual and simulated gravity-magnetic fields using this program in a modern interface.