The invention concerns a gradiometer comprising two SQUIDs, each of which contains a SQUID loop. The object of the invention is to provide a gradiometer of this type wherein increased measuring accuracy of the magnetic field or of the magnetic field gradient is attained in a comparatively simple manner. To this end the gradiometer comprises SQUIDs disposed relative to one another such that the SQUID loops lie in a plane at a distance of a basic length from one another and a flat flux concentrator (FT1, FT2), parallel to this plane, surrounds the two SQUID loops. A flux concentrator is further provided which is mirror-symmetrical laterally to the base line interconnecting the centres of the two SQUID loops. Advantageously a given desired basic length can be set by suitable structural measures without increasing the inductance and thereby reducing the gradiometer signal.
