Table of Contents
- How Do You Know You Need Glasses
- Glasses Prescriptions
- At-Home and Online Tests
- Tests to Gauge Overall Eyesight
- Reading Glasses for Presbyopia
- Tips to See Better
- See Your Doctor Regularly
If your vision has changed recently, you may need glasses to improve your sight.
Getting regular eye exams, especially after you turn 40 years old, means you have consistent monitoring of your vision changes over time and better prescriptions to suit your needs.
If you do not have the time to get an eye exam and are concerned about your vision changes, an online or printable at-home test may help you get an idea of your vision change, but it cannot diagnose your vision with full accuracy.If you are middle aged or older, you could also get over-the-counter reading glasses to improve your vision.
However, the best way to take care of your eyes is to be diagnosed by an eye doctor.
How Do You Know You Need Glasses?
Eyeglasses are one of the oldest methods of correcting vision problems. A frame holds two glass or plastic lenses that modify how light refracts into your eye, so you can see clearly despite a refractive error.
Glasses are among the most common forms of eyewear to correct sight, adding or subtracting power to manage nearsightedness (myopia), farsightedness (hyperopia), misshapen corneas (astigmatism), or farsightedness associated with age (presbyopia).
Most people develop vision problems as they get older, but for many people, refractive errors begin in childhood. Often, eye diseases like glaucoma and cataracts manifest refractive errors, so you may initially think your eyesight is getting worse due to age.
Because there are several potential causes of changing vision, it is important to go to an optometrist for a full eye exam, diagnosis, and referral to other practitioners if necessary. You may be able to understand some of your vision problems on your own, thanks to the internet, but again, a professional exam is always recommended.
Glasses Prescriptions: How Your Vision Correction Is Measured Over Time
When you visit an optometrist, they will measure each eye strength separately because the human eye changes at different rates.
The Federal Trade Commission (FTC) monitors optometrists and ophthalmologists through the Eyeglass Rule and the Contact Lens Rule, requiring your eye doctor to give you your lens prescription at the end of the exam for no additional fee, whether or not you ask for a prescription for glasses or contact lenses. You can take your prescription to any provider of glasses or contact lenses, including online services, and you should never be required to fill this prescription at your specific optometrist’s office.
The power of your eye’s visual strength is measured in diopters, reflecting the amount of change in lens shape needed to clearly focus images onto your retina. As your vision changes, diopter measurements will adjust by 0.25 as the standard increment. Your eyes are referred to differently.
- Oculus dexter is the right eye, abbreviated as RE.
- Oculus sinister is the left eye, abbreviated with LE.
These terms come from Latin root words, but you may see them on your prescription to indicate your eyes. You may also see measurements.
- Sphere: This number reflects your nearsightedness or farsightedness. This will appear on your prescription as “S.”
- Cylinder: This number indicates level of astigmatism, which changes the shape of the eye from round to cylindrical. Your prescription reflects this measurement as “C.”
- Axis: This number measures the degree of astigmatism. This word will be written out on your prescription.
The typical format for writing these numbers on your prescription is S x C x Axis.
Since hyperopia, myopia, and astigmatism change the cornea and the rest of the eye’s shape in different ways, you will need different lens shapes to refract light. These shapes include:
- This shape is thin at the center and thicker at the edges, which helps to adjust nearsightedness. Prescription diopters have a “-“ sign in front of them.
- The opposite of concave, convex lenses are thickest at the center and thinner at the sides to correct farsightedness — either hyperopia or presbyopia. Prescription diopters have a “+” in front of them
- These lenses typically curve more in one direction than another to correct for astigmatism.
Even if you have “perfect” vision — or 20/20 vision, meaning you can see clearly 20 feet away from you — you should still undergo annual eye exams to maintain your eye health. Eye health can reflect general health, and comprehensive visual exams every year can show if there are changes in your cornea, retina, fluid pressure, and other important parts of your eye.
If you do not have any previously diagnosed eye conditions, you should consider getting eye exams at certain frequencies based on age.
- Babies: The first eye exam should occur at 6 months old, with another at 12 months (1 year).
- Children: Between 3 and 5 years old, the child should go in for an eye exam at least once. Then, the child should have an eye exam at 6 years old or before first grade. Eye exams should be annual after that until age 18.
- 20 to 39 years old: If you have no preexisting eye conditions, including refractive errors, you should get an eye exam at least every 5 years.
- 40 to 54 years old: Once you reach middle age, it is important to have eye exams every 2 to 4 years because several vision changes begin at this point in your life even if you have not had vision problems before.
- 55 to 64 years old: Eye exams are needed every 1 to 3 years to monitor your eye health for serious conditions, including cataracts.
- 65 and older: Getting an eye exam every 1 to 2 years monitors progressing eye changes for older adults.
Your optometrist or ophthalmologist will perform several tests during your routine eye exam to determine if your eyes are changing, how much they are changing, and why.
Many people are choosing to check their eyes online instead of going to an eye doctor. This process can get you started, but optometrists and ophthalmologists have tools at their disposal that allow for more thorough diagnoses.
At-Home and Online Tests Cannot Diagnose Underlying Conditions
There are a few charts that can be used online to get a general idea of your visual problems or changes.
For example, color vision charts can accurately tell you whether you have colorblindness or not; however, these tests do not provide treatment, and they are not a legitimate prescription. You will still need to see a medical professional to understand how colorblindness may be associated with your general health.
While you can use online tests to give you a general idea, you still need to see a professional to get a diagnosis.
Online Tests That Can Help You Gauge Your Overall Eyesight
The American Academy of Ophthalmology (AAO) offers help to perform tests at home for children or adults and get the most accurate readings possible. Here are some online tests to consider:
- Snellen eye chart: Sit 10 feet away from a printed or onscreen Snellen Eye Chart, which starts with a large “E,” and record which lines you are able to read without any visual correction. Then, cover one eye and read the lines; cover the other eye and read the lines; and record your results. Your eyes most likely have minor differences.
- Diopter reading test: You may also consider a printable diopter reading test, which you will then hold 14 inches away from your eyes. Attempt the top line, which has the smallest print, without any glasses or contact lenses; continue down the chart until you can find a line that you can read clearly. The number to the right of the line indicates what prescription power you need. If you need less than +3.00, you may be able to find reading glasses over the counter.
- Additional tests: There are other vision tests available through several online companies, including one for astigmatism, but professional eye doctors question the accuracy of these tests. Still, many of the services will offer to send your results to a professional optometrist or ophthalmologist in your area for review after you pay a small fee. If you choose not to pay the fee, but do notice that you have poorer vision than you expected, this indicates that you should see an eye doctor in person.
Again, it’s incredibly important to see an eye doctor in person. Most people develop a refractive error at some point, but sometimes, conditions like glaucoma or cataracts can cause changes in your vision. These conditions must be monitored, or you can go blind.
Reading Glasses for Presbyopia: Over the Counter or Prescription?
If you have presbyopia and have not developed other refractive errors earlier in life, your optometrist may recommend purchasing over-the-counter reading glasses. Typically, your optometrist will recommend reading glasses power based on your age.
- 40 to 44 years old: You will use a power between +0.75 to +1.00 diopters to adjust your presbyopia.
- 45 to 49 years old: Typically, this age group will need +1.00 to +1.50 diopters.
- 50 to 54 years old: As presbyopia continues, this age range will need between +1.50 and +2.00 diopters.
- 55 to 59 years old: For this age group, +2.00 to +2.25 diopter reading glasses are typically recommended.
- 60 years old and older: For older adults, +2.25 to +2.50 diopters can adjust more progressed presbyopia.
Nonprescription reading glasses are sold over the counter with powers up to +3.00. After passing this convex lens number, you will need a prescription for reading glasses. Experts recommend that you pick the reading glasses with the lower power if you have two pairs of OTC glasses that correct your vision in about the same range. Wearing corrective lenses that are too powerful, even a little bit, for your eyes can cause eye strain, headaches, and make your vision worse faster.
You should also consider getting several pairs of reading glasses with different powers to help you perform different tasks, including working on a computer, watching television, and driving.
Over-the-counter reading glasses, or readers, may work for you for a little while, but if you find that OTC glasses improve your vision, you should get a comprehensive eye exam soon. This exam means you can get a prescription for glasses. Your vision will be accurately corrected based on unique biological factors.
Reasons you will need to see an optometrist for a prescription instead of purchasing OTC glasses include:
- Your pupils may not line up with store or online glasses, so you need a custom fit.
- You have an underlying medical condition that changes your refractive error faster than average.
- You have different diopter powers in each eye. OTC reading glasses have the same power in each eye, but most people naturally develop slightly different powers in each eye as their vision changes.
- You have astigmatism, which OTC reading glasses do not correct for.
OTC glasses are made with less precision and tend to be lower-quality glass. These distortions can cause long-term problems with your eyesight.
Top Glasses Retailers & Brands
Today, you have a plethora of options available when it comes to glasses.
Here are some of the top retailers where you can find a variety of brands:
- Warby Parker: This popular eyeglass retailer offers high-quality glasses from a variety of manufacturers.
- GlassesUSA: This company offers both designer and more affordable options in its large online inventory. GlassesUSA features a wide range of frame and lens types.
- Eyeglasses.com: This retailer features a wide array of glasses options, including frames at a variety of price points.
There are hundreds of eyeglass brands. Some of the most popular options include the following:
- Kate Spade
- Ted Baker
- Ray Ban
Tips to Help You See Better
While reading glasses may be needed, there are other steps you can take to improve your ability to read.
- Increase the text or font size on your phone, computer, tablets, and electronic reading devices.
- Use high-contrast text on your electronic devices. Check the settings on your phone or tablet to see if this is an option on your device.
- Improve the lighting in your home, office, and work areas.
See Your Doctor Regularly
Overall, it is best to see an optometrist every few years or as soon as you have questions or concerns about your vision quality. It is likely that you have a normal refractive error, but you may have a different condition in your eyes. You may need a different approach than over-the-counter reading glasses to help you.
Establishing a relationship with an optometrist or ophthalmologist means you can have your vision monitored by professionals as you age. This is incredibly important.
Eyeglasses for Vision Correction. (December 12, 2015). American Academy of Ophthalmology (AAO).
Prescription Glasses and Contact Lenses. (April 2016). Federal Trade Commission (FTC) Consumer Information.
Eyeglasses and Contact Lenses. University of Rochester Medical Center, Health Encyclopedia.
How to Read Your Eyeglass Prescription. (December 7, 2017). WebMD.
20/20 Vision? Why You Still Need an Eye Exam. Aetna Health Insurance.
Recommended Eye Exam Frequency for Pediatric Patients and Adults. American Optometric Association (AOA).
Home Eye Test for Children and Adults. (December 21, 2016). American Academy of Ophthalmology (AAO).
All About the Eye Chart. (February 2021). American Academy of Ophthalmology (AAO).
Find Your Reading Glasses Power. The Fine Print Blog.
The Doctor Will “See” You Now: Online vs. In-Person Vision Tests. (March 15, 2018). CNN.
What is the most common reading glasses strength? ›
1.00 reading glasses
This is one of the most commonly-bought reading glasses strengths. It's the prescription to pick if you only have slight problems reading small letters.
45 to 49 years old: Typically, this age group will need +1.00 to +1.50 diopters. 50 to 54 years old: As presbyopia continues, this age range will need between +1.50 and +2.00 diopters. 55 to 59 years old: For this age group, +2.00 to +2.25 diopter reading glasses are typically recommended.What readers strength do I need? ›
Someone who needs strong vision correction will likely need reading glasses with a strength around +3.00, while someone who needs only minor vision correction would likely wear reading glasses with a label of +1.25. For most people new to needing readers, it's highly unlikely that they'll need a high powered lens.How do I know the power of my glasses? ›
A minus sign before the number indicates that you are nearsighted, while a plus sign means that you're farsighted. Lens power is measured in diopters. The higher the number, the stronger the prescription. For example, “-5.00” written under sphere means that you are very nearsighted and need a five diopter correction.Are reading glasses just magnifiers? ›
A common misconception about reading glasses is that they magnify small print. Actually, they make it easier to read small print by providing the correct diopter strength which usually begins at +0.75 all the way up to +4.00 (more on that later).Do cheap reading glasses damage your eyes? ›
If you don't already need to wear regular eyeglasses, they may even be fine for longer. But cheap readers only magnify the print to help you read it. They are not specific to your individual eye's needs. They probably won't harm your eyesight, but you may experience headaches and eye strain if you use them too much.What is 2.50 reading glasses? ›
If your prescription reads -1.00, that means your eyeglasses need 1 diopter of strength to correct nearsightedness. If your prescription reads +2.50, your eyeglasses need 2.5 diopters of strength to correct farsightedness. The higher the number, the more correction your vision needs.What does 2.25 mean for glasses? ›
If your number is between -0.25 and -2.00, you have mild nearsightedness. If your number is between -2.25 and -5.00, you have moderate nearsightedness. If your number is lower than -5.00, you have high nearsightedness.How do I know what reading glasses I need from my prescription? ›
To get the right number, you need to do a little math. To find the right reading glasses, add the sphere number to the ADD number. In the above example, for the right eye, this would be -2.00 and +1.75, which equals -0.25. For the left eye, add +1.00 and +1.75 to get +2.75.Can you wear reading glasses all day? ›
Wearing reading glasses all the time won't harm your eyes' health, but you may get a headache from wearing them while driving, playing sports, or other activities that involve a wider scope of vision. It's important to get the right glasses for your particular circumstances.
Can you wear reading glasses to watch TV? ›
Ask your optician's advice if you have prescription lenses – they may recommend wearing your glasses for watching television, especially if you wear your glasses for distance tasks. An antireflection coating may also improve visual comfort and reduce eye strain.What is normal power of eye? ›
20/20 vision is normal vision acuity (the clarity or sharpness of vision) measured at a distance of 20 feet. If you have 20/20 vision, you can see clearly at 20 feet what should normally be seen at a distance.What is the lowest strength for reading glasses? ›
Reading glass power is measured in units called diopters. The lowest strength is usually 1.00 diopters. Glasses go up in strength by factors of . 25 (1.50, 1.75, 2.00).What does 1.25 mean on reading glasses? ›
1.00 stands for one diopter. However, the correction can be measured in one-quarter diopters. For example, 1.25 is one and one-quarter diopters. Typically, the further away from zero, the stronger the prescription. For example, 3.50 means that more correction is needed in comparison to a 2.25.How can you tell if your glasses prescription is wrong? ›
- Blurred Vision. One of the most obvious signs that your eyeglasses aren't correcting your vision like they should is fuzzy and unclear eyesight. ...
- You're Squinting A Lot. ...
- Your Eyes Feel Tired. ...
- Your Eyes Are Sensitive To Light. ...
- You're Getting Frequent Headaches.
- Print or purchase a vision chart. ...
- Tape the chart on a wall. ...
- Place your child's chair ten feet away from the chart.
- Ask your child to cover one of his or her eyes. ...
- Light the vision chart. ...
- Have your child read each line of the chart. ...
- Repeat the process with your child's other eye covered.
What is the normal eye SPH, CYL, and Axis value? Normal eyes would typically have about 0.50 dioptres of negative cylinder or cyl power at an axis number of 180. Typically, most people have between 0.5 to 0.75 dioptres of astigmatism and won't need contact lenses or glasses to see clearly.Are prescription reading glasses better than store bought? ›
Prescription glasses will perform better and are tailored to your vision needs. It may not hurt to have a pair of OTC readers available to put on as a backup, but in the end, it's best to get prescription.What's the difference between prescription glasses and reading glasses? ›
Standard reading glasses are only designed to view objects at close range, which is why bifocals are commonly used to shift between short range and distance vision. Reading glasses are not designed to correct vision problems, and unlike prescription glasses, are not designed for full-time use.What is the difference between reading glasses and distance glasses? ›
Distance glasses provide an entirely different function than reading glasses. Distance glasses are used for myopia to correct distance vision which is anything beyond arm's length. Reading glasses are used for hyperopia and presbyopia to correct close vision with 35cm from your face.
Why is my vision blurry after using reading glasses? ›
Both your eyes and brain need time adjusting to prescription glasses. Some people adjust to this change in a matter of days while others may take weeks to adapt. When it's new glasses causing blurry vision or a new prescription number in old lenses, you have to give yourself time to adjust.Can you just buy any reading glasses? ›
“You do not need a prescription to buy reading glasses,” he adds. “Non-prescription readers do of course still have a specific lens magnification, typically ranging from +0.25 to +6.00, called a 'power' or 'strength.Are reading glasses all the same? ›
Aside from different colors and styles, reading glasses come in different strengths. Which you should use depends on your vision and habits.What is considered a strong prescription for glasses? ›
-3.00 diopters or less is mild. -3.00 to -6.00 diopters is moderate. -6.00 to -9.00 diopters is severe. -9.00 diopters or more is extreme.Is 2.00 A strong prescription? ›
The difference between mild and severe nearsightedness is just a few inches. Those with mild nearsightedness (-2 prescription) start to have blurry vision for objects more than 20 inches away, and those who are very highly nearsighted (-8 prescription) start to see blur for objects more than 5 inches away.How do I know what reading glasses I need from my prescription? ›
To get the right number, you need to do a little math. To find the right reading glasses, add the sphere number to the ADD number. In the above example, for the right eye, this would be -2.00 and +1.75, which equals -0.25. For the left eye, add +1.00 and +1.75 to get +2.75.What does 1.25 mean in reading glasses? ›
1.00 stands for one diopter. However, the correction can be measured in one-quarter diopters. For example, 1.25 is one and one-quarter diopters. Typically, the further away from zero, the stronger the prescription. For example, 3.50 means that more correction is needed in comparison to a 2.25.Is there an online test for reading glasses? ›
Online Eye Test by Luxreaders
At Luxreaders, we offer two vision tests. Our simple, indicative vision test helps you with a quick overview to identify the strength you need when buying reading glasses. Our more in-depth and newest online vision test which is developed by us, is also available.
At this point, inexpensive “Over-the-Counter” reading glasses can be used to help you read. These temporary OTC readers may not be perfect, but they are harmless to wear and often provide good reading vision. They are sold at optical shops, and at most drug, grocery, and department stores.Are prescription reading glasses better than over the counter? ›
While OTC glasses may be cheaper and easier to buy, they are not the best option in the long run. Everyone should have regular eye exams to check for conditions like glaucoma and cataracts. Prescription glasses will perform better and are tailored to your vision needs.
What is the difference between reading glasses and prescription glasses? ›
Standard reading glasses are only designed to view objects at close range, which is why bifocals are commonly used to shift between short range and distance vision. Reading glasses are not designed to correct vision problems, and unlike prescription glasses, are not designed for full-time use.What does +0.75 mean in glasses? ›
A plus sign would mean they are farsighted. This second number, -0.75, indicates the person has an astigmatism, which is a distortion in the shape of the cornea that causes blurred vision.What is the average eye power? ›
Having 20/20 vision means you have normal or average, vision. Some people have vision that's better than 20/20, like 20/15 vision or 20/10 vision. This means that you can see something 20 feet away (like a line on an eye chart) that most people can see when they're 15 feet away (20/15) or 10 feet away (20/10).What's the lowest prescription for reading glasses? ›
Reading glass power is measured in units called diopters. The lowest strength is usually 1.00 diopters. Glasses go up in strength by factors of . 25 (1.50, 1.75, 2.00).Is there a big difference between 1.25 and 1.50 reading glasses? ›
The higher the number of diopters, the stronger the power of the glasses. That means +1.50 diopters are stronger than +1.00 diopters. Or, put another way, the higher the number, the closer you'll be able to see.Should I wear reading glasses on my phone? ›
If you're having trouble reading text messages on your cell phone, reading glasses can help. If you have complaints, e.g. headaches when working on the screen, you may need blue light filter glasses. However, this is not a long-term solution.What is a good prescription for eyes? ›
A prescription number of +1.00 or -1.00 indicates that a minimal prescription change is needed. In comparison, +4.00 or -4.00 means you need a stronger prescription to see clearly. If you notice changes in your vision, such as difficulty reading signs or seeing objects clearly, contact your eye doctor for an eye exam.Does Medicare pay for a new pair of glasses after cataract surgery? ›
Part B covers certain doctors' services, outpatient care, medical supplies, and preventive services. helps pay for corrective lenses if you have cataract surgery that implants an intraocular lens. Corrective lenses include one pair of eyeglasses with standard frames or one set of contact lenses.Do you get a free pair of glasses after cataract surgery? ›
Medicare will pay for one pair of post-cataract surgery glasses per lifetime per eye after cataract surgery.Do you lose your close up vision after cataract surgery? ›
It is very common to have blurry or unclear vision in the days and sometimes even weeks after cataract removal. Most of the time, this is caused by normal swelling in the eye which occurs as a part of surgery.