Reading Glasses Strength Guide: How to Find the Best Readers for You

If you’re over 40, you might be noticing a reduced ability to see and read things up close. While this can be frustrating, it’s a completely normal part of the aging process and something everyone experiences as they get older.[*] 

The gradual loss of your ability to see close-up objects clearly is called presbyopia. It typically becomes noticeable in your early to mid-40s and worsens until age 65 or so.[*] Presbyopia is not harmful in any way, but it’s undeniably annoying. 

Fortunately, there’s an easy solution for up-close vision loss: reading glasses (aka readers)! So, how do you know if you need reading glasses and what strength readers you should get? This guide breaks down how to find the best reading glasses for you.

Do You Need Reading Glasses?

There are a number of signs and symptoms that can help you know if it’s time to get reading glasses. These include:

• Struggling to read smaller print, especially in dim light
• Finding yourself holding things like books, menus, and your phone farther away from your face to read them
• Squinting to try to see things up close
• Experiencing eye strain and/or headaches after reading or doing close-up work 

Both non-prescription (aka over-the-counter) reading glasses and prescription reading glasses  (which require a prescription from an eye doctor) eliminate the above symptoms, although their methods are different. Non-prescription reading glasses magnify up-close objects, whereas prescription reading glasses bend light as it enters your eye, allowing it to focus directly on your retina.

The Basics of Reading Glasses Strengths

Reading glasses are labeled with different numbers, which represent the glasses’ strength. The strength is measured in units called diopters, which describe the corrective power of a lens. The higher the number, the stronger the power of the glasses. So, for example, +2.5 diopters are stronger than +1.00 diopters. 

Next to the number, you’ll notice a “+” sign, which represents farsightedness (the inability to see close up). If you don’t see a “+” symbol, you can assume the glasses are for farsightedness, as glasses for nearsightedness are always marked with a “-” symbol.

What Are the Highest and Lowest Strength Readers Available?

The strength of non-prescription reading glasses typically ranges from about +1.00 to +3.00. Non-prescription reading glasses can be purchased online or at various retail stores and have the same strength in both lenses.

Prescription reading glasses are available in higher strengths (up to about +4.00) and can be customized to fit the exact prescription of your eyes, even if one eye is stronger than the other.

Prescription glasses also correct issues like astigmatisms and are available in multi-focal options for people who need near, intermediate, and far vision assistance in one pair of glasses.

How Do You Know What Reading Glasses Strength to Get?

So, how can you ensure you’re choosing the right strength reading glasses—ones that will allow you to effortlessly read and see up close? Let’s review the different ways.

Visit an Optometrist

The most surefire way to guarantee you choose the correct strength reading glasses is to visit an optometrist who can test your vision and tell you the exact strength you need for each eye. An optometrist can also detect issues like astigmatism. 

Once the optometrist has examined your eyes, they’ll provide you with a customized prescription that you can use to order glasses online or at retail store. 

Use a Reading Glasses Strength Test Chart

If you’re not able or ready to visit an optometrist, you can use an at-home eye chart to get an idea of the reading glasses strength you need. To do this, follow these simple steps: 

Step #1: Print out our Reading Glasses Strength Chart

Step #2: Hang the chart on a wall 14 inches from your face 

Step #3: For this step, remove any corrective contact lenses or glasses. Cover one eye and start reading the chart from top (smallest text) to bottom (largest text). 

Make note of the first line you can clearly read and the number next to this line. This number indicates the strength that will likely best serve you. You may need to go down several lines before you can read a line clearly. Repeat this process for the other eye. 

If your two eyes need different magnification strengths, choose a strength that is in between the two.

Visit an In-Person Store 

Another quick and easy way to get an idea of the strength you need is to visit an in-person store to try on over-the-counter reading glasses. Bring a book and try on glasses with different strengths. 

Once you find the pair that helps you see text the most clearly, make note of the magnification strength. If two pairs of differing strengths appear to help similarly, choose the pair with the lowest magnification.   

Use an Age Chart  

Using an age chart is likely the least accurate way of all the methods—everyone is different, after all—but it can be informative in a pinch. 

The following is a reading glasses strength chart by age. It details generalizations about the strength of reading glasses needed at certain ages.

What To Do If Your Reading Glasses Stop Working As Well?

Up-close vision worsens with age. This means that the pair of reading glasses you got when you were 45 will most likely not provide the same clarity when you’re 55. 

If you notice that your trusty readers aren’t working as well as they once did, this usually means you need a new pair of glasses with a higher strength. As mentioned earlier, it’s best to visit an optometrist to determine your precise strength requirement, but you can also use the above methods to get a good idea of the new strength you need. 

Refer to the strength of your current pair of readers, which is usually marked on the inside of one of the temples (arms), when shopping for a new pair of readers. Many people find that increasing by +0.25 or 0.50 diopters does the trick when updating to a higher magnification.