The present disclosure relates generally to systems and methods for determining the refractive error of a patient, more particularly determining the patients refractive error by using a computerized screen, and providing a prescription for the patients preferred type of corrective lenses. In a general embodiment, the present disclosure provides a method for determining a corrective lenses prescription of a patient. The method includes, separately, for each eye of the patient, determining an astigmatism prescription for the patient via a computerized screen and without the use of a refractor lens assembly, including instructing the patient to move a known, fixed distance away from a computerized screen and testing for a cylinder component by sequentially presenting at least two cylinder diagrams to the patient via the computerized screen and enabling the patient to select at least one input per cylinder diagram, where those inputs correspond to cylinder measurements for determining the prescription.