How do I read my glasses prescription?

Learn how to read your glasses prescription (Rx). When know what the optical terms and abbreviations mean, your prescription is easy to understand.

Glassesgallery lens info image - Prescription information

Glassesgallery lens info image - PD1

DISTANCE VISION (DV) & NEAR VISION (NV)

  • Distance Vision: Also known as being farsighted, longsighted or hyperopia. Closer objects appear to be blurred.
  • Near Vision: Also known as being nearsighted, shortsighted or myopia. Nearsighted means that with your natural uncorrected vision, you can see close or "near" objects but those further out get blurry.

PD icon

PUPILLARY DISTANCE (PD)

Your PD is the distance between your pupils. PD is used to center lenses correctly over your eyes.
  • Monocular PD: PD measurement written as two numbers e.g. 32/33
  • Binocular PD: PD measurement written as one number (if the left and right side have been added together) e.g. 65

Glassesgallery lens info image - SPH

SPHERE (SPH)

Sphere indicates the amount of lens power prescribed to correct nearsightedness or farsightedness. If the number has a minus sign (-), you are nearsighted; if the number has a plus sign (+) or there's no plus or a minus sign, you are farsighted.

Glassesgallery lens info image - CYL

CYLINDER (CYL)

Cylinder indicates the amount of lens power for astigmatism. If nothing appears in this column, you have no astigmatism, or yours is so slight that it is not necessary to correct it.

Glassesgallery lens info image - Axis

AXIS

Axis describes the lens meridian that contains cylinder power to correct astigmatism. The axis is defined with a number from 1 to 180. If your eyeglass prescription includes cylinder power, it also must include an axis value. It comes after the cylinder power and is preceded by an "x" when written freehand.

Glassesgallery lens info - add

ADD

Add is the added magnifying power applied to the bottom part of multifocal lenses to correct presbyopia. The number always appears with a plus sign, and even if it doesn't, it's understood as a "plus" power. It usually ranges from +0.75 to +3.00 D and will be the same power for both eyes.

Glassesgallery lens info image - OD

O.D. and O.S.

OD and OS are Latin abbreviations. Oculus means eye, dexter means right and sinistra means left in Latin. OD stands for right eye. OS stands for left eye.

Glassesgallery lens info - prism

PRISM

Prism is the amount of prismatic power. It's prescribed to compensate for eye alignment problems. It's not commonly found in glasses prescriptions. When present, it is indicated in either metric or fractional English units (0.5 or ½, for example). The direction of the prism is indicated by noting the relative position of its "BASE" or the thickest edge. Four abbreviations are used for prism direction: BU = base up; BD = base down; BI = base in (toward the wearer's nose); BO = base out (toward the wearer's ear).

Looking for Stylish Glasses?

Are you paying hundreds of dollars for a pair of decent progressive lenses? Why not experience progressive lenses offered by Glasses Gallery that guaranteed visual comfort for FREE ! Once you try, you will never want to change to another pair , Learn more ……
First time here at Glasses Gallery? Register now and get an extra 15% off on frames!
If you find a better price on any pair of eyeglasses or sunglasses, we will beat that price! If you find a pair of glasses that beats our price, we will match their price, and offer an additional $3 off.
We are confident that you will love your purchase from us, but if for any reason you decide not to keep the product, you are eligible for full purchase value store credit, an exchange or a refund towards your method of purchase. Learn More …
Quick Start Guide
Upload Prescription
Lens Fitting Service
PD Measurement
How to Choose a Frame
Order Return
Order Tracking
Adjust your Glasses