A microelectromechanical gyroscope includes: the support structure; a sensing mass, coupled to the support structure with degrees of freedom along a driving direction and a sensing direction perpendicular to each other; and a calibration structure facing the sensing mass and separated from the sensing mass by a gap having an average width, the calibration structure being movable with respect to the sensing mass so that displacements of the calibration structure cause variations in the average width of the gap. A calibration actuator controls a relative position of the calibration structure with respect to the sensing mass and the average width of the gap.