Surface Magnetic Field refers to the magnetic flux density measured at a specific point on the surface of a magnet. It is expressed in units of Gauss (Gs) or Tesla (T), where 1 T = 10,000 Gs. Because the magnetic field strength varies across different areas of a magnet’s surface, the value commonly referred to as the “surface magnetic field” usually represents the magnetic flux density at the center of the working surface of the magnet. Measuring Surface Magnetic Field