How to Read Eyeglass Prescription For Reading Glasses

How to Read Eyeglass Prescription For Reading Glasses

If you have ever looked at an eyeglass prescription, you might probably wonder how to read eyeglass prescription for reading glasses. Worldwide, these prescriptions are written in a standardized format with some common notations. Here, we help you with a walk-through on how to read eyeglass prescriptions.

What Do The Numbers On Prescription Mean?

What Do The Numbers On Prescription Mean

Eyeglass prescription contains lots of numbers; you might not be familiar with those numbers and letters. Here is what the numbers are meant for:

Right Eye (OD) and Left Eye (OS)

(OD) and (OS) is an abbreviation of oculus dexter and oculus sinister; this is the Latin term for the right eye and left eye. Besides, eyeglass prescription has a column labeled OU. This abbreviation also a Latin term for oculus uterque, which means the “both eye.” 

 Sphere (SPH)

The sphere number indicates that if you are nearsightedness or farsighted and the amount of correction required for your eyes. A minus sign you find next to the number means nearsightedness, and a plus sign is a farsightedness, which means you might need a reading glass. Lens power is measured in diopters (D). Usually, the further away you get from the zero on either the plus or minus side, the stronger your prescription is.

 Cylinder (CYL)


The cylinder indicates how much lens power astigmatism you need. If the column appears nothing, that means you have no astigmatism or little astigmatism, which entails correction. 

If there any number in the cylinder column may be preceded with a plus sign, which is farsighted correction astigmatism or a minus sign for nearsighted astigmatism. Cylinder power constantly follows the sphere strength in your eyeglass prescription.

ADD Number

The ADD number of +1.75 speaks the power that should be “added” to the separation remedy to give the patient an unmistakable vision at a close range for perusing and close point exercises.


Axis is also written as X. the number between 0 and 180 correspond to astigmatism orientation. The number 90 represents the eye’s vertical meridian, and the number 180 represents the horizontal meridian.

If cylindrical power includes in your prescription, the axis value must include the prescription, which follows the cylindrical power and is preceded by an axis when written by hand.

An Example Of An Eyeglass Prescription

Below, I will share an eyeglass prescription:

OD – 2.00 SPH +2.00 add 0.5 p.d. BD

Operating system – 1.00 – 0.50 x 180 +2.00 add 0.5 p.d. BU

For this situation, the eye specialist has recommended – 2.00 D circle to remedy myopia in the right eye (OD). There is no astigmatism rectification for this eye, so no chamber force or hub is noted. This specialist has chosen to add “SPH” to affirm the correct eye is being endorsed just spherical force. (A few specialists will add “DS” for “diopters circle;” others will leave this territory clear.)

An Example Of An Eyeglass Prescription

Now, you have realized how to read eyeglass prescription for reading glasses. I suggest taking care of your eyes, and if you want to learn something more, visit