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A system has been developed to measure spherocylindrical spectacle lenses. The global pandemic limited access to regular eye exams. The system bypasses this limitation by providing at-home prescription measurements. The power and orientation of the spectacle lenses are obtained with a cell phone camera, a displayed or printed target, and a magnetic stripe card. The spatially varying magnification of the lenses is calculated by examining the image captured through the lens of the target at a fixed distance. This information is then used to calculate a clinical prescription, i.e., Sph/Cyl × Axis. The system is tested with 48 single-power spherocylindrical lenses with a range of −11.25 to þ4.25 D for Sph, −5.25 to −0.25 D for Cyl, and a whole range of Axis. The results are plotted in comparison with these reference prescriptions provided by a commercially available lensmeter and show good agreement. The image processing and clinical prescription calculation are discussed here.