A device for measuring an angle at which a magnetic field is aligned in a plane relative to a reference axis has at least two magnetic field sensors, which are aligned with their measurement axes in and/or parallel to the plane and oriented at right angles to each other. The device has a PLL phase control circuit with a follow-on oscillator arranged in a phase control loop, which has at least one oscillator output for a digital oscillating signal. The magnetic field sensors are coupled to the phase control loop in such a way that the digital oscillating signal is phase synchronous with a rotation scanning signal formed by rotary scanning of the measurement signals of the magnetic field sensors. The oscillator output is connected to a phasing detector for determining the phasing of the digital oscillating signal.