The results of three-dimensional modeling of the magnetic field distribution of permanent magnets were presented. The developed method for modeling the magnetic field distribution of the permanent magnet with the set geometric parameters was also given. For three-dimensional modeling, open source software ElmerFem, where calculations were performed by the finite element method was used. Experimental studies of the distribution of the magnetic field, originating from real magnets, in order to verify the model used in modeling were conducted. Correction of the model used in modeling was carried out based on the experimental studies. Verification of the developed method by modeling and measurement of permanent magnets was also performed. The results of experimental studies and theoretical modeling were almost identical, which validated the developed method for modeling the magnetic field distribution of permanent magnets. The developed method can be used in solving applied problems of calculating the three-dimensional distribution of magnetic fields of permanent magnets, which are used in designs of electric machines, electromagnetic transducers.