OD / OS
OD means right eye; OS means left eye.
PRESCRIPTION GUIDE
Your prescription, translated.
The abbreviations on an eyeglass prescription are a compact way to describe the correction your lenses need. This guide helps you read the essentials before you order.
Read the prescription key
READ IT IN THIS ORDER
The key details, at a glance.
Your eye-care professional writes the prescription; this is simply a plain-English guide to the most common fields you will see when entering it.
EyeSideSPHCYLAXIS
ODRight eyeSphere powerAstigmatism detailAngle
OSLeft eyeSphere powerAstigmatism detailAngle
SPH
Sphere is the main lens power. A minus sign generally indicates nearsighted correction; a plus sign generally indicates farsighted correction.
CYL & AXIS
These usually appear together when astigmatism correction is prescribed. If CYL is blank, AXIS may be blank too.
ADD
An additional near-vision power sometimes included for multifocal prescriptions.
PRISM
A specialist correction that should be entered exactly as written on your prescription.
PD
Pupillary distance is often recorded separately. Find a careful way to confirm it before ordering.
BEFORE YOU ORDER
Use the prescription you have now.
Enter the values exactly as your eye-care professional has written them. If a detail is unclear, or the prescription has expired, pause and contact your prescriber rather than guessing.
Find your PD