To improve the production qualities of a steel mill, in-mold electromagnetic stirrers (M-EMS) are generally implemented at the continuous casting process to provide the desired stirring forces to remove those undesired inclusions and bubbles during the metal solidification. As the system is mainly operated by interaction of induced eddy currents and composite traveling electromagnetic fields in the molten metal, inputs of stator currents and structures of M-EMS will dominate the entire system performance. Assisted by three-dimensional (3-D) finite-element analysis (FEA) and flux path modeling refinements, a compact analytical model with sufficient accuracy that can adequately predict the time-averaged performance of the M-EMS system at various structure- and material-compositions will be devised. From these confirmed operational indices, a convenient assessment tool for on-site operation and maintenance of the M-EMS at the metal industry has been successfully established.