Find your reading glasses strength
Read a few lines at true size on this screen. In about two minutes you get a suggested strength, checked against your age.
Before you start
Tick anything that applies to you. If nothing does, continue.
Please see an eye doctor soon. These signs need an exam, not reading glasses. You can still take the test, but do not rely on it.
Set up
- Take off your reading glasses. Keep contacts or distance glasses on if you normally wear them.
- Turn the screen brightness up and sit in good light.
- Hold the screen 14 in (35 cm) from your eyes. Use a ruler or tape measure the first time.
- Set your screen size so the print is the right size.
Can you read this clearly?
Both eyes open, no squinting, screen at 14 in (35 cm).
The morning train leaves from platform nine.
She keeps a spare key under the blue flower pot.
Fresh bread and coffee were waiting on the table.
The museum is closed on the first Monday of the month.
He wrote the phone number on the back of an envelope.
Take two tablets with a full glass of water after meals.
The ferry crosses the bay every forty minutes in summer.
Please check the expiry date printed under the barcode.
Our garden has tomatoes, basil, mint and three apple trees.
Turn left at the old stone bridge and follow the river path.
The small print says the offer ends at midnight on Friday.
Line 1 of 11
Your result
Suggested strength
Good to know
- Try the strength on in a store before buying, with something you actually read.
- Test each eye by covering the other. If the eyes give different results, see an eye doctor.
- Test again in a year. Most people need a little more strength every few years until about 65.
This is a screening aid, not an eye exam. It cannot detect eye disease.
Reading glasses strength by age
A starting point if you only know your age. The test above is more personal.
| Age | Typical strength |
|---|---|
| 40 to 44 | +1.00 – +1.25 |
| 45 to 49 | +1.25 – +1.75 |
| 50 to 54 | +1.50 – +2.00 |
| 55 to 59 | +1.75 – +2.50 |
| 60 to 64 | +2.00 – +2.75 |
| 65 and over | +2.25 – +3.50 |
Ranges span the age charts published by two large US readers brands. See the full chart and sources.
How the test works
Reading glasses come in steps of a quarter diopter, usually from +1.00 to +4.00. The weaker your close-up focus, the larger the print has to be before you can read it without help. The test uses that link. It shows lines of print in +1.00 to +3.50 sizes and asks which is the smallest you can read clearly at 14 in (35 cm).
- Set the screen size. Screens differ, so the same print can look large on one phone and small on another. Hold a bank card against the screen and match the outline once. After that every line is drawn at its true size.
- Hold the screen at 14 in (35 cm). That is normal reading distance. A few inches closer or farther changes the result, so measure it the first time.
- Read the lines. Start with the largest. Say yes only when the words are sharp without squinting.
- Get your result. You see a suggested strength, the usual range for your age, and the strength for a computer screen.
How accurate is it?
Expect the result to be within a quarter or half diopter of what suits you. That is close enough to pick a pair to try on, which is how store-bought readers are meant to be chosen. Printed charts from different brands do not agree with each other on print sizes, and no home chart replaces an exam.
The test cannot tell whether your eyes are healthy, whether you have astigmatism, or whether each eye needs a different strength. An eye doctor checks all of those. If you have not had an eye exam in the last two years, book one, even if readers solve the small-print problem.
Other ways to find your strength
- Strength chart by age: a quick estimate from your age alone.
- Strength calculator: work it out from a glasses prescription, for a computer, or from your near point.
- Printable chart: the same chart on paper.
Questions about reading glasses strength
What strength reading glasses do I need?
Most people start at +1.00 to +1.50 in their early forties and move up by about a quarter diopter every few years, reaching +2.50 or more in their sixties. Your own number depends on your eyes and how far away you read. Take the test above for a personal estimate, or look at the strength chart by age.
How do I know what strength reading glasses I need at home?
Hold a diopter chart 14 in (35 cm) from your eyes without glasses and find the smallest line you can read clearly. The strength printed beside that line is your starting point. This page does that on your screen at true size. You can also print the chart.
Can I do a reading glasses test on my phone?
Yes. Set the screen size with a bank card first, because phone screens vary a lot. Then hold the phone 14 in (35 cm) away and read the lines. Turn the brightness up and take the test in good light.
How accurate is an online reading glasses test?
It usually lands within a quarter or half diopter of the strength that feels right, as long as the screen size is set and the distance is measured. It is a way to choose which pair to try, not a prescription. It cannot find astigmatism, a difference between your eyes, or eye disease.
How do I determine reading glasses strength from my prescription?
Add the ADD number to the sphere (SPH) number for each eye. A sphere of +0.50 with an ADD of +1.75 gives +2.25 readers. If your sphere is 0.00 or blank, the ADD alone is your readers strength. The strength calculator does this and warns you when store-bought readers will not suit your prescription.
What is the lowest strength of reading glasses?
Most store racks start at +1.00, and some brands sell +0.75, +0.50 and even +0.25, mostly online. See the lowest strength reading glasses.
Should I pick the higher or the lower strength if I am between two?
Pick the lower one. Readers that are too strong make you hold things closer and can cause eye strain and headaches. Go up a step only if print is still hard to read after twenty minutes or so.
How far away should I hold the chart?
14 in (35 cm). That is the distance the print sizes are designed for and about where most people hold a book or a phone. If you read at a different distance, use the calculator to adjust.
What strength reading glasses do I need for a computer?
Less than for a book, because the screen is farther away. As a rule of thumb it is about half your reading strength. The result of the test shows a figure for your own screen distance. More in reading glasses for computer use.
What if my two eyes need different strengths?
Store-bought readers have the same strength in both lenses. If covering one eye and then the other gives results that differ by more than a quarter diopter, see an eye doctor. Prescription reading glasses can be made with a different lens for each eye.
Do I need reading glasses at all?
If you hold your phone farther away to read it, need brighter light than you used to, or get tired eyes after close work, and you are past 40, probably yes. See do I need reading glasses for the full list of signs.
How often should I test again?
Once a year is enough. Near focus keeps weakening slowly until about age 65, so most people move up a quarter diopter every two or three years. A sudden change is different: see an eye doctor.
Is this an eye exam?
No. It is a screening aid for choosing non-prescription reading glasses. Eye doctors recommend a full exam around age 40 and regular exams after that, because conditions such as glaucoma have no early symptoms.
- Do I need reading glasses?
- How do reading glasses work?
- What is a diopter?
- What is the lowest strength of reading glasses?
- Reading glasses for computer use
- Reading glasses after cataract surgery
- Reading glasses with contacts
- Can you wear reading glasses all the time?
- Do reading glasses weaken your eyes?
- Are reading glasses FSA or HSA eligible?