How to read an eyeglasses prescription

Learn everything about your prescription
in this short video tutorial

Your glasses prescription is a series of numbers, usually in a chart, that describe the lenses needed to correct your vision. This chart has two rows, one for your right eye and one for your left. Four columns are used to precisely describe your correction.

Watch our prescription video guide

Understanding your prescription

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Let's translate the abbreviations.

SPH or Sphere

SPH or Sphere

Refers to the amount of spherical error for your eyes, measured in quarters and proceeded by a (+) or (-).

CYL or Cylinder

CYL or Cylinder

Describes astigmatism, a refractive error that causes distorted and blurred vision, measured in quarters and proceeded by a (+) or (-).

AXIS

AXIS

Indicates the orientation of astigmatism, measured in degrees 1 to 180.

ADD or NV

ADD or NV

Meaning Near Vision is used for multifocal or reading correction, measured in quarters. This power for bifocal or progressive lenses enlarges immediate vision and is therefore always indicated by a positive sign (+).

O.D.

O.D.

Refers to the right eye.

O.S.

O.S.

Refers to the left eye.

PD or Pupillary Distance

PD or Pupillary Distance

Refers to the distance in millimeters between the center of one pupil to the center of the other.

Enter your prescription

 
Sphere (SPH) ?
Cylinder (CYL)?
Axis?
Addition (near) ADD?
Right Eye (OD)
Left Eye (OS)
  • Pupillary Distance (PD):?  
  • Save this prescription as:
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