Sphere (SPH): This number indicates the degree of nearsightedness (-) or farsightedness (+) correction needed. It’s measured in diopters and can range from -10.00 to +10.00.

Cylinder (CYL): This number indicates the degree of astigmatism correction needed. It’s also measured in diopters and can range from 0.00 to -6.00.

Axis: This number indicates the orientation of the cylinder correction needed to correct astigmatism. It’s measured in degrees from 1 to 180.

Pupillary Distance (PD): This measurement is the distance between the center of each pupil, measured in millimeters. It typically ranges from about 54mm to 74mm.

Prism: This number is used to correct double vision, and is measured in prism diopters.

Base Curve: This measurement determines the curvature of the lenses needed to fit your eye.

It’s important to get an up-to-date prescription from your eye doctor before ordering eyeglasses or contact lenses. Your prescription should include all the necessary information for your eyewear, and you should also have your pupillary distance (PD) measured, which is not always included in the prescription. This information will help ensure that your glasses or contacts provide the correct level of correction for your eyes.