This talk will review the importance of magnetic analysis on circuits. This presentation includes a better and faster method to measure magnetic property for analysis of EV/HEV charging. It defines the method of computation of magnetic properties from in-circuit voltage and current which give real world results. This shows how B and H values can be computed using input voltage and currents. Derivation of key magnetic parameters such as maximum flux density, coercivity, retentivity and permeability from BH Curve is illustrated with waveforms captured from oscilloscope. This talk illustrates how hysteresis loss can be computed from the BH curve.