Reading Glasses Guide: How They Work & How to Choose the Right Pair

If menus, books, labels, or your phone are becoming harder to see up close, reading glasses may help.

Reading glasses provide additional focusing power for near vision. They’re commonly used as people develop presbyopia, a normal age-related change that makes it more difficult for the eyes to focus on nearby objects.

But not all reading glasses are the same. Some people can use ready-made readers, while others need prescription reading glasses that account for differences between the two eyes, astigmatism, or other parts of their prescription.

This guide explains how reading glasses work, what the numbers such as +1.00 and +2.00 mean, how prescription readers differ from over-the-counter readers, and when progressive lenses may make more sense.

Quick Answer

Reading glasses are designed to make close-up tasks easier to see.

They may help with:

• Reading books
• Looking at your phone
• Reading menus and labels
• Sewing and crafts
• Other close-up work

Reading glasses commonly use plus powers such as:

+1.00, +1.50, +2.00, or +2.50

A higher plus number generally provides stronger near focusing assistance.

However, the correct reading prescription isn’t determined by age alone. Your existing distance prescription, astigmatism, working distance, and differences between your eyes can all affect what you need.

If you have an eyeglass prescription from your eye doctor, use that prescription rather than guessing your reading power.

1. What Are Reading Glasses?

Reading glasses are glasses designed specifically for near vision.

They’re typically used for activities performed relatively close to you, such as reading a book or looking at your phone.

Unlike distance glasses, which are designed primarily to help you see farther away, reading glasses focus on a closer working distance.

This means something important:

Distance vision may look blurry while you’re wearing reading glasses.

That doesn’t necessarily mean the reading prescription is incorrect. Reading glasses are intended for close-up use.

2. Why Do People Need Reading Glasses?

One of the most common reasons is presbyopia.

Presbyopia is a normal age-related change in the eye’s ability to focus at close distances.

When you’re younger, the natural lens inside your eye can change shape relatively easily to focus on nearby objects.

Over time, that focusing ability decreases.

You may begin noticing that:

• Small print is harder to read.
• You hold your phone farther away.
• You need brighter light to read comfortably.
• Your eyes feel tired after close-up work.
• Reading becomes more difficult toward the end of the day.

Presbyopia commonly becomes noticeable sometime after age 40, although the timing and amount of correction needed vary from person to person.

3. What Do +1.00, +1.50, +2.00 and +2.50 Mean?

The number on reading glasses represents lens power measured in diopters.

For example:

• +1.00
• +1.25
• +1.50
• +1.75
• +2.00
• +2.50

As the plus number increases, the lenses provide greater focusing power for near vision.

For example, +2.00 is stronger than +1.00.

However, stronger isn’t automatically better.

Using more power than you need can make your comfortable viewing distance too close and may make the glasses less useful for the task you’re trying to perform.

4. How Do I Know What Reading Glasses Strength I Need?

The most accurate approach is to have an eye examination and use the prescription provided by your eye doctor.

This is particularly important if:

• Your eyes require different prescriptions.
• You have astigmatism.
• You already wear prescription glasses.
• Your vision has recently changed.
• You experience headaches or eye discomfort.
• One eye sees noticeably differently from the other.

Age-based reading charts can provide rough estimates, but they can’t account for your complete prescription.

Two people of the same age may need completely different reading prescriptions.

5. What Is ADD on an Eyeglass Prescription?

If you have a prescription for bifocals or progressive lenses, you may see a value labeled:

ADD

ADD stands for additional power.

It represents the additional plus power needed for near vision relative to your distance prescription.

For example, a prescription might show:

SPH: -2.00
ADD: +2.00

That does not necessarily mean you should simply order +2.00 reading glasses.

The ADD value is combined with your distance prescription to determine the appropriate near prescription.

This is one reason people who already have a distance prescription shouldn’t automatically use their ADD number as their reading-glasses power.

6. How Is a Reading Prescription Calculated?

A reading prescription generally incorporates your distance prescription plus the prescribed near addition.

Here’s a simplified example:

Distance prescription:

SPH: -1.00
ADD: +2.00

The resulting near spherical power may be:

-1.00 + +2.00 = +1.00

But real prescriptions can also include:

• Cylinder (CYL)
• Axis
• Prism
• Different prescriptions for each eye

Those values also need to be handled correctly.

If your doctor has provided separate distance and reading prescriptions, use the specific prescription intended for the glasses you’re ordering.

7. Prescription Reading Glasses vs. Over-the-Counter Readers

The inexpensive reading glasses sold at pharmacies and stores are generally ready-made readers.

They commonly have the same spherical power in both lenses.

For example:

Right eye: +1.50
Left eye: +1.50

That may work well for someone whose eyes have relatively similar needs and who doesn’t require correction for astigmatism or other prescription components.

Prescription reading glasses can account for:

• Different right and left eye prescriptions
• Astigmatism
• Cylinder and axis
• Prism when prescribed
• Your specific pupillary measurements
• Other prescription requirements

If your prescription is more complex, prescription reading glasses provide much more customization than generic readers.

8. What Is Astigmatism and Why Does It Matter for Readers?

Astigmatism is a common refractive condition that can cause blurred or distorted vision.

On an eyeglass prescription, it’s typically represented by:

CYL and AXIS

Ready-made reading glasses generally don’t correct an individual’s astigmatism prescription.

If your prescription includes meaningful cylinder and axis values, custom prescription readers may provide clearer vision than generic readers.

9. Can Each Eye Have a Different Reading Prescription?

Yes.

It’s completely normal for the right and left eyes to have different prescriptions.

For example, one eye might require:

+1.25

while the other requires:

+2.00

Ready-made readers usually can’t accommodate this because both lenses typically contain the same power.

Prescription reading glasses can be made individually for each eye according to your prescription.

10. Reading Glasses vs. Distance Glasses

The major difference is the distance they’re designed to help you see.

Reading Glasses

Designed primarily for close-up activities such as:

• Books
• Phones
• Labels
• Crafts
• Close detail work

Distance Glasses

Designed primarily for farther-away vision, such as:

• Driving
• Television
• Signs
• Movies
• General distance viewing

If you’re wearing dedicated reading glasses, your distance vision may become blurry.

That is expected because the lenses aren’t designed for distance viewing.

11. Reading Glasses vs. Progressive Lenses

Reading glasses generally provide one prescription across the entire lens, optimized for near vision.

Progressive lenses contain multiple viewing zones within one lens.

They typically provide:

• Distance vision toward the top
• Intermediate vision through the middle
• Near vision toward the bottom

This allows you to look between different distances without constantly removing your glasses.

Reading glasses may make sense if:

You primarily need glasses for close-up tasks and don’t mind removing them when you’re finished.

Progressives may make sense if:

You need correction at multiple distances and want one pair of glasses for everyday use.

Neither option is automatically better.

They serve different needs.

12. Reading Glasses vs. Bifocals

Bifocal lenses contain two distinct viewing areas.

Typically:

• The upper portion is for distance.
• The lower portion is for near vision.

Traditional bifocals usually have a visible line separating these areas.

Progressive lenses also provide multiple viewing distances but transition gradually without the traditional visible bifocal line.

Dedicated reading glasses, by comparison, generally use near correction throughout the entire lens.

13. Can I Wear Reading Glasses All Day?

If they’re dedicated reading glasses, they’re usually intended for near tasks rather than continuous general viewing.

Wearing them while looking farther away may make your distance vision blurry.

You may find yourself repeatedly:

• Taking them off
• Looking over them
• Moving them down your nose

If you constantly switch between near and distance viewing, progressive or bifocal lenses may be more convenient.

14. Can You Drive With Reading Glasses?

Dedicated reading glasses aren’t designed to provide clear distance vision.

You shouldn’t rely on reading-only glasses for driving if they make your distance vision blurry.

If you require distance correction for driving, use glasses prescribed for that purpose.

Progressive or bifocal lenses may allow someone who needs both distance and near correction to use one pair, depending on their prescription and eye doctor’s recommendations.

15. What Are Computer Reading Glasses?

Computer screens are usually farther away than a book or phone.

That means glasses optimized for very close reading may not necessarily provide the most comfortable vision at computer distance.

A computer-specific prescription can be designed around your typical working distance.

This is sometimes referred to as:

• Computer glasses
• Intermediate glasses
• Office glasses
• Occupational lenses

If your normal readers make your computer screen blurry unless you move unusually close, the reading prescription may simply be optimized for a shorter distance.

16. Does Reading Distance Matter?

Yes.

Lens power and working distance are related.

Someone reading a book relatively close to their face may have different visual requirements from someone viewing a desktop monitor farther away.

When discussing reading glasses with your eye doctor, it can help to explain what you’ll actually use them for.

Examples include:

• Reading books
• Phone use
• Desktop computer
• Sewing
• Music
• Crafts
• Detailed professional work

For specialized tasks, your preferred working distance can matter.

17. Can Reading Glasses Make Your Eyes Weaker?

Using appropriately prescribed reading glasses doesn’t make your eyes “lazy” or cause presbyopia to progress because you started wearing them.

Presbyopia naturally changes with age.

People sometimes associate stronger reading prescriptions with wearing readers because their near vision continues to change after they begin using them.

The glasses aren’t necessarily causing that change.

18. Why Are My New Reading Glasses Blurry?

First determine where the vision is blurry.

Distance is blurry, but reading is clear

This may be completely normal for dedicated reading glasses.

They’re designed for near vision.

Reading is also blurry

Possible reasons include:

• Incorrect prescription
• Incorrect working distance
• Incorrect lens power
• Prescription entry error
• Astigmatism not being corrected
• Incorrect measurements
• A changed prescription

If your reading vision isn’t clear at the intended distance, verify the prescription and contact your eye doctor or eyewear provider if necessary.

19. Why Do I Have to Hold Things Farther Away?

Holding reading material farther away is one of the classic signs that near focusing is becoming more difficult.

People sometimes joke that their “arms aren’t long enough anymore.”

Moving the object farther away temporarily reduces the focusing demand on your eyes.

If you consistently find yourself extending your arms to read small print, it may be time for an eye examination.

20. Should I Buy Readers or Get an Eye Exam?

Ready-made readers can be convenient for some people with straightforward near-vision needs.

However, reading difficulty can also occur alongside other vision changes.

An eye exam can determine:

• Your actual prescription
• Whether your eyes require different powers
• Whether you have astigmatism
• Whether you need distance correction
• Whether another type of lens would be more appropriate

Regular comprehensive eye examinations are also important for reasons beyond determining reading-glasses strength.

Common Mistakes When Buying Reading Glasses

Avoid these common mistakes:

• Choosing reading strength based only on age.
• Assuming stronger readers are always better.
• Using the ADD number as the reading prescription without considering the distance prescription.
• Assuming both eyes have the same prescription.
• Ignoring astigmatism.
• Expecting reading glasses to provide clear distance vision.
• Ordering reading glasses when you actually need progressives.
• Using very close reading glasses for a computer positioned farther away.
• Copying someone else’s reading-glasses strength.
• Continuing to increase reader strength without having your vision checked.
• Entering a distance prescription as a reading prescription.
• Assuming all reading glasses are the same.

Frequently Asked Questions

What strength reading glasses do I need?

The appropriate strength depends on your eyes, existing prescription, and intended working distance. An eye examination provides the most accurate answer.

Is +2.00 stronger than +1.50?

Yes. +2.00 provides more plus lens power than +1.50.

What does +1.50 mean on reading glasses?

It means the lenses have +1.50 diopters of spherical power.

At what age do people usually need reading glasses?

Presbyopia commonly becomes noticeable after about age 40, but the timing varies.

Why can’t I see far away with my reading glasses?

Dedicated reading glasses are designed for near vision. Distance blur while wearing them can therefore be expected.

Can I use my ADD number to buy reading glasses?

Not necessarily. ADD represents additional near power relative to your distance prescription. Your actual reading prescription may need to combine those values.

Are prescription readers better than drugstore readers?

Prescription readers can correct differences between your eyes, astigmatism, and other prescription requirements that generic readers usually can’t. Some people with simple, similar prescriptions in both eyes may find ready-made readers adequate.

Can one eye need +1.00 and the other +2.00?

Yes. Your eyes don’t necessarily require identical prescriptions.

Do reading glasses correct astigmatism?

Custom prescription reading glasses can include cylinder and axis correction for astigmatism. Standard ready-made readers generally don’t provide individualized astigmatism correction.

Can reading glasses hurt your eyes?

An inappropriate prescription may cause uncomfortable or blurry vision, but reading glasses don’t normally damage healthy eyes simply from being worn.

Should I get reading glasses or progressives?

Reading glasses are useful when you primarily need near correction. Progressives may be more convenient if you need correction for multiple distances throughout the day.

Why can I read my phone but not my computer with my reading glasses?

Your computer may be farther away than the distance your reading prescription is optimized for. You may need a different intermediate or computer prescription.

Do reading glasses make your eyesight worse?

Reading glasses don’t cause the normal age-related progression of presbyopia.

How often should I replace my reading glasses?

Replace them when your prescription changes, the lenses or frames become significantly damaged, or they’re no longer providing comfortable vision.

Key Takeaways

Reading glasses are designed specifically to help with near vision.

Powers such as +1.00, +1.50, and +2.00 indicate increasing amounts of plus lens power, but choosing the strongest pair isn’t the goal.

The correct prescription depends on your individual eyes and how you’ll use the glasses.

Ready-made readers may work for people with straightforward near-vision needs, while prescription reading glasses can account for differences between the eyes, astigmatism, prism, and other prescription requirements.

And remember:

If reading is clear but distance becomes blurry while you’re wearing dedicated reading glasses, that can be completely normal.

Reading glasses are made for reading—not for seeing every distance.

Need More Help?

Not sure whether you need reading glasses, distance glasses, or progressive lenses?

If you have a current eyeglass prescription, Choice Eyewear can help you understand which lens option matches what your doctor prescribed before you place your order.