Compass calibration

A system, method, and computer program product are provided for calibrating a sensor device, such as an accelerometer, gyroscope, and/or magnetometer. The sensor device provides measurements, and a determination if the sensor device is in a steady state is made based at least partly on the measurements. If the sensor device is in a steady state then measurement data is stored in a memory, and the sensor device is calibrated at least partly with the stored data. A set of such steady points is gathered with the sensor device in various spatial orientations, preferably with the steady point orientations spaced appropriately apart to ensure precise calibration throughout the range of possible orientations. Calibration parameters are determined by fitting the set of steady point measurements to an ellipsoid. Active audio and visual guidance may be provided to a user to assist with orienting the sensor device during calibration.