The highest performance magnets are rare earth magnets, NdFeB rare earth magnet and is the most powerful magnets. However, at 200 degrees Celsius environment, is the most powerful samarium cobalt magnets.

Determining the performance of the magnet can be a magnetic energy product BH by: representing the magnetic energy density in the air gap space magnets (two pole magnet space) established, i.e., the static magnetic energy per unit volume of the air gap. As this energy is equal to the product of the magnet Bm and Hm, so called energy product. Magnetization of the permanent magnet surface to a specified location: magnetic field: space on the magnetic poles of the magnetic effect of the surface magnetic field