A system and method of determining a magnetic field and magnetic compass calibration is disclosed. One embodiment is a method of determining a magnetic field vector, the method comprising storing, for each of a plurality of sensor orientations, one or more calibration components, determining, for a sensor orientation not included in the plurality of sensor orientations, a magnetic field vector and a gravity vector, iteratively estimating one or more calibration coefficients based on the stored components, the determined magnetic field vector, and the determined gravity vector, wherein the calibration coefficients are updated during each of a plurality of iterations, and determining a sensor-orientation-independent magnetic field vector based on at least one of the calibration coefficients.