Postoperative lens position is predicted on the basis of known measured values, such as the corneal thickness, the depth of the anterior chamber, the eye length, and the distances of the capsular bag equator and/or of the lens haptic from the anterior surface of the lens. In addition, the calculation also takes into account the attitude of the intraocular lens, for which purpose additional parameters of the pseudophakic eye are used that have not previously been taken into consideration. The proposed method is suitable for a more exact prediction of the strength and nature of an intraocular lens to be implanted in a pseudophakic eye in the context of cataract surgery or of a refractive intervention. The method is based on the use of suitable calculation methods, e.g. geometric optical formulae, or of ray tracing.