How To Read Your Glasses Prescription?

How To Read Your Glasses Prescription?

How to read your glasses prescription has no hard and fast rule. Let's say you went for your regular eye checkup. The doctor provides glasses prescription with sphere vs cylinder. Are you perplexed? Trying to figure out what (+) and (-) means? What on the earth is this OD, OS? Are you having issues while trying to decipher how intense is your eye health? Let's find out what SPH and CYL means on your eye prescription. Because without this how would you find a perfect pair of contact lens? Find the right frame and lower the chances of further complexity in your eye health. All you need to learn is how to read glasses prescription. Worry not, we have broken down each step for you. Let's find out what the abbreviations and numbers mean on your eye prescription typically.

Glasses Prescription

Optimal vision is achieved with the proper interpretation of glasses prescription. Glasses prescription are basically encoded to provide precision of vision correctness. Learning how to read your glasses prescription is necessary. Because each abbreviation and number stands for a specific aspect of vision correctness. So you need to know which area of your eye needs proper medical attention. Apart from this, you don't have to rely on your scheduled check-ups only. Glasses pescriptions should be up-to-date. The precision of your vision is achieved with a new glasses prescription. Visit an eye specialist the moment you feel eye discomfort. This way you'll avoid the potential eye damage/risk. 

How To Read Your Glasses Prescription? Is it important?

Glass prescriptions are written or digital ordered from an eye specialist. They are important because you get to know the specific lens required to correct your vision. You also tend to make informed decisions about your eyewear. Whether you have short-sightedness or far-sightedness (SPH or sphere), astigmatism (CYL or cylinder and AXIS), also an ADD for additional power while reading or writing. Without knowing how to read your glasses prescription, it gets difficult for you to select the frame according to your preference. 

Eye Comfort

Better visual acuity is what determines the overall eye health. Correct lenses ensure improved reading, writing, and driving, reducing strain on eyes and chances of accidents.

Reduced Eye Strain

Optimal performance of your eye can only be achieved with the right pair of lenses. For this, you have to know how to read your glasses prescription. Once you know the root cause. You can find a lens that does justice to your eye condition. The wrong lens will promote strain, cause itching and headache in your eyes.

Enhanced Vision

Enhancing vision is only possible when you know what lens power is needed. The lens power for short-sightedness, farsightedness, astigmatism is what determines your optimal vision with improved clarity and sharpness.

What Is Included In An Eyeglasses Prescription Form?

An eyeglass prescription form consists of grids, columns, and rows. The fusion of number, signs, and abbreviations altogether perplexes a human mind. Let us teach you the meaning of each element written on your eyeglasses prescription. Once you understand. Imply your knowledge of how to read your glasses prescription on the eye prescription chart below. Let's delve into the visionary knowledge of glasses prescription!

What is a diopter?

A Diopter is the unit that measures the refractive power of a lens. It is the reciprocal of the focal length. It denotes farsightedness (hyperopia) and near-sightedness (myopia). The dioptric measurement on eyeglasses prescription is indicated by SPH. 


If you know how to read your glasses prescription, know that SPH (-) means nearsightedness. Nearsightedness indicates a person has no issue visualising near objects. So it means difficulty seeing far objects. The more positive the number (-2.00, -2.05), the more intense the nearsightedness.


If you know how to read your glasses prescription. Know rhat SPH (+) means farsightedness. Farsightedness indicates a person has no issue visualising far objects. So it means difficulty seeing nearby objects. The more positive the number (+2.00, +2.05), the more intense the farsightedness.

What does pl mean on eye prescription?

Pl on an eye prescription means there's a clean bill of eye health. Learn how to read your glasses prescription and find out pl means ‘plano’. This means there's no refractive error correction needed. If SPH column has pl written, this means there's no farsightedness or nearsightedness correction needed. If CYL has pl written, it indicates, there's no astigmatism correction needed for vision.

What do OD and OS mean?

Let's find out what OD and OS means:

OD indicates Oculus Dexter, which means ‘right eye’ in Latin.

OS indicates Oculus Sinister, which means ‘left eye’ in Latin.

What are sph cyl and axis in eye prescription?

Sph, cyl, and axis denote specific details in your refractive error of the eye. Let's break down these elements and find out what they mean:


SPH denotes farsightedness or nearsightedness. (+) means farsightedness and (-) means nearsightedness. The higher the number, the greater difficulty in seeing respective objects.


Cyl denotes the degree of the cornea being sphere. This condition is known as astigmatism. It could be a positive or negative number.


Axis is a number between 0-180. It indicates the orientation of astigmatism which tells the cylindrical correction of the eye lens.

What is an add on glasses prescription?

Add denotes the addition and is for older age adults. The loss of eye lens flexibility causing presbyopia (difficulty focusing close object) If you know how to read a glasses prescription. It would be clear that this means additional power in the diopter. Allowing you to focus on close-up objects.

What do the prescription instructions “+” and“- ”mean for eyeglasses?


Positive sign in SPH column of eye prescription means farsightedness (hyperopia) difficulty seeing near objects.


Negative sign in SPH column of eye prescription means nearsightedness (myopia) difficulty seeing distant objects

What do the prescription instructions “+” and“- ”mean for eyeglasses


How long is the expiration date on a prescription order?

You cannot simply sit and wait for your head to ache, your vision to blur, or your eye to cause discomfort. Eye prescriptions should be renewed. This means you have to get your eyes checked every year. Prevention is better than cure. So regular eye check-ups are recommended. It is possible for you to see things clearly for a while. But in the long run, your eye health will deteriorate.

Making sure your eye health is up-to-date and accurate keeps your eyesight intact. As you learn how to read your glasses prescription. It gets mandatory for you to know the expiration date of your eye prescription with sphere vs cylinder distortion in vision. So, don't wait for you eye prescription to hit that expiry date. Get yourself prepared for a new checkup and identify the moderation or severity of your eye health today!

How can I buy eyeglasses if I don't have a prescription order?

Okay, you know how to read your glasses prescription. But is it possible for you to get an eyewear without an eye prescription? No. You cannot simply go to your optician. Tell how you're having difficulty seeing near objects and get your perfect eyewear. You need to go to an optometrist. Let him observe you under eyesight machines with digits. This tells whether you've (+) or (-), astigmatism, SPH or CYL. You cannot simply sit at your home and come to know how severe your eyesight problem is.

Since you know how to read your eye prescription. Now follow these steps. Have your eye prescription in your hand and find the perfect pair of lenses with a comfortable frame.

Visit Eye-Specialist

Book your appointment to an opthamologist/optometrist today. He'll figure out the vision, refractive errors in your eye and then provide a bill of your eye health. Visit an eye technician with this up-to-date prescription. 

Read Your Eye Prescription

How to read your eye prescription involves no math. These rows, columns, and grid. The  abbreviations, digits, and cells won't be a nightmare to you. 

Choose Frames

A variety of frames are there in market. Go for a frame that fits the contact lens. A frame that looks stylish and suits your preference.

Consider Lens Options

Considering lens is very crucial. The SPH and CYL needs to meet your vision requirements. The anti-reflective coatings, photochromic lenses, and high-index material within the lens should be given attention. 

Check Pupillary Distance (PD)

Pupillary Distance is written usually on an eye prescription. But if its not written, ask your eye specialist to measure it for you. This way your lenses will have an accurate vision possible.

How do you measure your PD if your PD is not on the prescription?

Pupillary Distance is the distance between the pupil of your eyes. It determines the centre of your lens in a way that grants proper alignment to your contact lenses. You ensure the centre of your pupil aligns with the centre of your lenses. It is what determines the accuracy of your vision. There are two possibilities, whether your PD is written or not. If it's written, well and good. If not, either ask your doctor to measure it or you can also measure it at your home.


Method 1: How to measure PD? 

Stand forth a mirror. Now hold the scale against your forehead. Start the millimetres units of the scale from the centre of your right pupil. You don't have to rely on a single reading. Take multiple readings to find a single accurate measurement of your PD. This will ensure the accuracy of your contact lens. 

Note: DP is always measured in mm. Another point to keep in mind is. DP is mostly the nearest even number.

Method 2: How to measure PD?

Let your friend hold a scale against your forehead. Make sure the zero of the scale is at the centre of your right pupil. Count the digits of mm from right to left centre of pupil. Ask your friend for the measurement. Note it down on your eye prescription.

If you're having multiple different pupillary distances. The best solution is to go to an eye specialist. PD shouldn't be taken lightly. It greatly affects the vision with contact lens. Let your eye specialist measure your PD if it's not convenient for you to find the accuracy!

Can I use my glasses prescription for contacts?

Glass prescription and contact lens parameters aren't interchangeable. Glasses are far from your eyes while contact lenses sit right at the front of your eyes. You cannot simply learn how to read a glasses prescription and find out your ideal lens type. Specific parameters like axis, diameter, curve, and power determine your correct vision. Even the sphere vs cylinder brings about a huge difference in your visionary. So, it's essential to get your contact lens prescription with proper mentioning of these specific details ensuring your eyesight to be rightly treated with a correct pair of lenses.

How often do you need to have your eyes checked?

The eye check-ups depend upon the age, disease, and existing eye health. Children should have their eye test done after 6 months. And then after every 2 years. Adults need to go to an opthamologist every year if no vision impairment is there. Older adults need to visit the doctors annually because of the increased risk of eye infections, cataracts, glaucoma etc. People with risk factors and contact lenses wearers need to have more frequent visits to ensure accurate and intact vision. 


The advantage of scheduled eye examination not only guarantees eye comfort, proper vision, and other issues. It also detects the potential eye disease before it gets the chance to prevail and affect. You deserve optimal vision throughout your life. So, do favour to your eyes by running to your eye specialist when the pain/discomfort rises even in between scheduled check-ups. Consider Dollger for yoir ideal frames and get all the comfort. Learn how to read your glasses prescription with sphere vs cylinder and stay on the safe side, visioning the greatness of the world!

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