Abstract: The magnetostatic potential and magnetic field of a solid and hollow cylindrical magnet is calculated everywhere in space in terms of complete elliptic integrals. These expressions are calculated using an electromagnetic analogy with the electrostatic potential and electric field of two uniformly charged disks with opposite surface density. The analogy is employed to study intuitively the discontinuities and the dipolar approximation of the fields (H) over right arrow and (B) over right arrow. The range of validity of the dipolar approximation has been studied along the cylinder axis and in the midplane perpendicular to the cylinder axis, comparing them with the obtained general expression.