In this research, we uses low-frequency electromagnetic field software (Ansys Maxwell 16) to simulate two coil models with different shapes - rectangular and circular in wireless power transmission (WPT). Next, the equivalent model of the series-series (S-S) compensation circuit implemented for leakage inductance, simulated by software (Powersim, PSIM) to analyze the overall efficiency (η). In an inductive and loosely coupled transformer, the influences of coupling coefficient (K) and mutual inductance (M) characteristics, which caused by different coaxial heights (h) and misalignment distances (d) of the coils are discussed. As results for circular shape at coaxial height (h=10 mm), the K=0.800 and η= 98.91%, which are optimal values for all shapes. These excellent simulation performances indicate proposed transformer is a candidate for a low-cost chip for vehicle WPT applications.