Systems and designs for tuning a wireless power transfer system are provided, which may include any number of features. In one embodiment, a wireless power transfer system can include first and second switched capacitor circuits electrically connected to opposite poles of the inductor of a resonator in the wireless power system. The first and second switched capacitor circuits can be switched on and off with MOSFETS to change a capacitance of the circuits, and thus an effective capacitance of the resonator. Methods of use are also provided.