Devices, systems and methods for automatic calibration of rate gyroscope sensitivity are described. One exemplary method includes receiving a first plurality of measurements from a gyroscope and a second plurality of measurements from at least another sensor including at least one accelerometer, generating an orientation estimate of the device and a plurality of orientation corrections based on the first and second plurality of measurements, generating an estimate of a sensitivity of the gyroscope based on the orientation estimate, the plurality of orientation corrections and the first plurality of measurements, and calibrating at least the gyroscope based on the estimate of the sensitivity. In an example, the at least another sensor may include an accelerometer and/or a magnetometer.