The analysis of electromagnetic field in the system «inductor - bath of molten (liquid metal)" by different winding characteristics of the inductor due to analytical method is shown in this paper. Integral and differential characteristics of the system are defined and compared for the most common coil inductors MHD-stirrers. It provides a framework for the analysis of field harmonics on the surface of melt for various types of inductors. Also made the comparative assessment of influence of longitudinal edge effect on system performance.