Sound familiar: the text on your phone looks blurry; you keep holding the restaurant's menu further away, and reading a book before bed takes more effort than it did a few years ago. These are typical signs that your eyes could use a bit of help with close-up focus. And that quickly raises the next question: which reading glasses strength do you actually need?
Choosing the right reading glasses' strength sounds trickier than it really is. In this article, we walk you through how to determine your reading glasses' strength step by step, what to pay attention to while testing, and when it makes sense to visit an optician instead.
What does reading glasses strength actually mean?
The strength of reading glasses, also called diopter, shows how much magnification the lens adds so you can see clearly up close. Reading glasses always have a positive strength, roughly from +1.0 to +3.5. The higher the number, the stronger the magnification.
This is different from prescription glasses for distance vision, which correct short or long sightedness. Reading glasses are meant for people who, as they get older, start struggling to focus at close range, a completely normal process called presbyopia that usually begins around age forty.
How do you determine your reading glasses strength?
There are a few simple ways to get a good sense of the strength that suits you, before you make a final choice.
Try a reading glasses test
A reading glasses test at home is a great starting point. Grab a text in a normal font size, such as a book or newspaper, and hold it at your usual reading distance of around 30 to 40 centimeters. Then try out different strengths and notice which one lets you read comfortably and sharply, without squinting or having to hold the text further away. Our online strength test page walks you through this step by step and gives you a first indication of your strength.
Pay attention to your age
Age isn't an exact science, but it is a useful guideline. Most people first notice around age forty that reading up close becomes harder, and the strength needed then gradually increases as they get older. That's a normal part of ageing and nothing to worry about.
Recognise these signs?
Before you start testing, it helps to know exactly what to look out for. The following signs are the most common among people who need their first pair of reading glasses, or a stronger pair than the one they currently have:
- You hold your phone, book, or menu further away to bring the text into focus.
- Small print, such as on packaging or in leaflets, is hard to read without extra light.
- Your eyes feel tired or strained after half an hour of reading or needlework.
- You get a mild headache after an evening of reading or puzzling.
In dim light, such as in a restaurant, reading suddenly becomes noticeably harder.
Recognise one or more of these? Then chances are a pair of reading glasses, or a stronger strength than you currently wear, would help.
Which strength should you choose? Guidelines by age
The table below offers a general guideline based on age. These are averages, your personal situation may differ.
These guidelines are a good starting point, but the reading glasses test remains the best way to confirm your own strength. Want to know more about when seeing sharply with the right strength really makes a difference? Also read our guide on perfect visibility with the right strength.
Found your strength? Now pick your style
Once you know which strength suits you, choosing becomes the fun part. At Looplabb, ready-made reading glasses come in dozens of colours and frame shapes, from timeless black and tortoiseshell to bolder tones with a bit more personality. Since every frame is available in the same range of strengths, you can happily pick a few, a subtle one for the office and a colourful one for the weekend, without testing your strength again. Feel free to browse our full reading glasses collection to see which frame suits your style.
Difference between your left and right eye
For most people, the difference between the two eyes is minimal, which is why ready-made reading glasses with the same strength in both lenses work well for most people. However, if you notice you read noticeably better with one eye than the other, or if you have another eye condition alongside presbyopia, such as astigmatism, custom reading glasses from an optician are a better choice than ready-made ones.
What if the strength doesn't feel right?
A wrong strength is usually easy to spot. If you feel headaches, tired eyes, or still need to squint after a few minutes of reading, chances are the strength isn't quite right. If you find yourself holding the text further away than usual, the glasses are probably too strong.
Do give yourself a day or two to get used to new reading glasses, your eyes sometimes need a little time to adjust to the new focus. If the discomfort continues after that, try a step lower or higher in strength. It's also completely normal to move up a strength every so often as the years go by. That isn't a sign anything is wrong with your eyes, just a sign that presbyopia is slowly progressing, as it does for almost everyone.
A few practical tips to make testing easier:
- Always test in daylight or good indoor lighting, in dim light almost every strength will feel too weak.
- Use the same reading distance you normally hold, so don't move closer or further away on purpose.
- Test with a text you know well in terms of font size, such as a newspaper or book, rather than very small print.
- Torn between two strengths? Choose the lower one. A strength that's too high strains your eyes more than one that's slightly too weak.
Test it yourself or visit an optician?
For most people with ordinary, gradual presbyopia, ready-made reading glasses in the right strength are a great and affordable solution. Still unsure whether you need reading glasses at all? Our guide on when you need reading glasses is a helpful place to start.
A visit to the optician is worthwhile if discomfort continues despite a well-matched strength, if you notice a clear difference between your two eyes, or if you have other eye complaints such as blurry distance vision, double vision, or headaches that don't go away. In those cases, prescription reading glasses from an optician are the safer choice. Read more about when prescription reading glasses are worth it in our article on the benefits of prescription reading glasses.
Frequently asked questions about reading glasses strength
Can I just buy any strength of reading glasses?
Yes, for ordinary presbyopia without other eye conditions, you can choose ready-made reading glasses based on a test. Looplabb's reading glasses are available in strengths from +1.00 to +3.00, so you'll likely find yours in that range. If in doubt, go for the lower strength and try it out for a while.
Does my strength change over time?
Yes, most people need a slightly stronger pair every few years, until the strength typically stabilises around age sixty. It's a good idea to retest your strength every now and then.
Can I use the same strength for both eyes?
For most people, yes, since the difference between both eyes is usually minimal with ordinary presbyopia. If you notice a clear difference, consult an optician for custom reading glasses.
In conclusion
Choosing the right reading glasses strength starts with listening to your eyes: where does reading become difficult, and at which strength does focusing feel effortless again? Use the age guidelines as a starting point, run the test at your usual reading distance, and switch to an optician as soon as you're unsure or discomfort continues. That way, you'll read, work, and relax again with sharp vision, without unnecessary squinting or tired eyes.
Once you know your strength, it's time for the fun part: picking a frame that suits you. Browse our reading glasses collection and find the colour and style that fit you best.
