When you buy eyeglasses online, entering your eyeglasses prescription accurately when ordering your glasses is extremely important! Let’s look at a typical prescription card and take a moment to understand the basics of the different components:
RX cards may vary across regions, but there are generally accepted standards for the abbreviations and numbers that you'll see on your RX Card.
OD=Right Eye, OS=Left Eye
power is the basic “strength” of the lens, whether near-sighted or far-sighted. It is measured in 0.25 increments. When there is no distance correction present, it may be marked as OO, PL, or with the "infinity" symbol, which looks like an "8" on it's side. Please enter O/plano for these situations.
refers to something called an ‘astigmatism’ correction. It should be a number between +/-6, in 0.25 increments. Opthalmologists will often use positive (+) cylinder, while most Optometrists use negative (-). There is a BIG difference between the two so please pay close attention to the signs and enter your prescription exactly as it appears. Not all prescriptions have Cylinder (CYL)/AXIS values. If you don’t have astigmatism correction, doctors may leave it blank but they might also put SPH, 00, Plano, or DS which means sphere or Diopter Sphere. For these situations, please enter 0/plano in the drop down box.
refers to where the cylinder power should be aligned. Please note that Cylinder (CYL) and Axis are always provided together. For any value of Cylinder there must always be a value for Axis. Axis must be from 0-180 degrees. Make sure to select each eye's axis value exactly.
Eye doctors will often leave out the decimal point on the sphere, cylinder, and addition. For instance, -5 or -1 is understood as -0.50 and -1.00, +275 is +2.75. It is imperative to note the “plus” or “minus” symbols in your prescription and enter them accurately!! These symbols refer to near- or far-sightedness.
The “ADD” power area refers to the power of any bifocal, if present. We’ll discuss types of bifocal lenses later. Not everyone will have these “ADD” powers present.
In rare instances, some people may have values for “Prism” or “Decentration.” If you have these values, there will be an area provided to enter those details. If present, they are very important for an accurate and comfortable prescription!
Finally, anything that is left blank on your prescription card should be left blank on the prescription entry screen when ordering your glasses.