A magnetic field measuring device having a first semiconductor body having a surface formed in a first x-y plane, the first semiconductor body having on the surface two magnetic field sensors which are spaced apart and arranged along a first connecting line, and wherein the magnetic field sensors respectively measure a z-component of a magnetic field, and the x-direction and the y-direction and the z-direction are each formed orthogonally to each other. A first magnet is provided with a planar main extension surface formed in a second x-y plane and with a symmetry surface formed in an x-z plane, wherein the direction of magnetization extends substantially or exactly parallel to the main extension surface and substantially or exactly parallel to the plane of symmetry. The first semiconductor body and the first magnet are rigidly fixed to each other.