top of page
  • Oliver

Ordering Prescription Glasses Online: An Opticians Guide

Young girl wearing black plastic glasses

You haven't order prescription glasses online? Why not? All the cool kids are doing it! Or so it seems. Truth is, ordering a set of prescription glasses online represents less than 10% off all prescription glasses orders. It's not a shockingly impressive number but considering it was at 2% just 3 years ago, it's clear that consumers are feeling more comfortable buying their glasses online.

I have one concern: who's showing the consumer the right way to buy prescription glasses? Really. I've been helping people of all ages for over 15 years, and the fact that online retailers are doing very little to teach consumers how to select the right set of glasses is troubling to me. In fact, it's borderline disrespectful to the craft of ophthalmic dispensing. It's not as simple as having your prescription and PD handy.

If we take the advice of online retailers, the best way to find the right glasses is to base it off the size and shape of our head. Apparently, that's the most important thing to consider when purchasing a medical device which directly influences the performance of one of our most valuable senses; sight.

Frames first. That's the approach every online glasses retailer takes. Well, it's wrong. Very wrong. Virtual try-on and augmented reality are impressive, but still the wrong approach because frames are made to be the priority. It's like selecting tires for a car without considering the type of vehicle and terrain first.

I don't want people to suffer. It's bad enough that a recent report, which measured nearly 200 prescription glasses from various online retailers, showed that nearly half (44.8%) of all the glasses had incorrect prescriptions or safety issues. I can't just stand by and watch. I have to do something.

So here it is. A guide that will show you the right way to buy prescription glasses online. It's not perfect. There is still plenty of room for human error, but at least you'll have a better understanding of the science behind finding the right set of prescription glasses for you.

free printable pd ruler

Always start with the prescription

Anytime you're going to select a new frame it's best to start by looking at the prescription. If you have a simple prescription then you may not need to worry about this, but for those that have a power that is over a plus or minus 2 diopters, the frame choice will have a direct influence on the eyeglasses function, weight and cosmetic appearance.

High Minus (Nearsighted)

Being Myopic (aka Nearsighted) generally produces lenses with 3 distinct characteristics:

  • Thickness is concentrated on the outside edges of the lens

  • Flatter front surface curve (aka Base Curve)

  • Makes the wearers eye appear smaller than they really are

A high minus power is considered to be anything over -3.00 diopters.

Due to the increased thickness on the edges, round is the ideal shape. Not everyone likes round so rectangular shapes with rounded corners or tapered edges is the next best shape.


Avoid Going Too Wide: The wider the frame, the more thickness there will be.

Avoid Half-Rim: This style of frame often requires the lenses to be grooved and thus prevents the lenses from being produced as thin as possible.

Avoid Complete Rimless: Depending on the style of the rimless frame and the degree of your corrective power, you may be ineligible for this type of frame. The thickness of the lens may prevent a secure mount. Another reason this isn't a popular option is because the thickness has nowhere to hide; the full thickness of the lens is on display for all to see.

High Plus (Farsighted)

Hyperopia (aka Farsighted) generally produces lenses with 3 distinct characteristics:

  • Thickness in concentrated in the center of the lens

  • Steeper front surface curve

  • Makes the wearers eyes appear to be larger than they actually are

​If your prescription is over a +2.50 then you're getting into what would be considered a high plus power.

With the concentration of thickness in the center a small frame size will help but most of the weight and thickness will have to be managed through the lens material. for power under +3.00, polycarbonate can provide good results. Anything over +3.00, Hi-index 1.67 or 1.74 is suggested.


Avoid Half-Rim: This style of frame often requires the lenses to be grooved and thus prevents the lenses from being produced as thin as possible.

Avoid Complete Rimless: Depending on the style of the rimless frame and the degree of your corrective power, you may be ineligible for this type of frame. Rimless frames require a minimum edge thickness and so the lenses may need to be intentionally made thicker in order allow for a secure mount.


You can be nearsighted, farsighted or even have perfect vision and you'll eventually have Presbyopia. Presbyopia, also known as Age Related Farsightedness, typically starts around the age of 40.​​ Our eyes would normally accommodate to focus on objects up close but as we get older this becomes more difficult. When the time comes, your doctor will prescribe an Additional Power (Add Power).

You will have to choose between these 4 options:

  • Progressives

  • Bi-focals

  • Tri-focals

  • Single Vision Reading


Avoid "Shallow" Frames For Multifocals: An optician can usually fit a multifocal into just about any frame but you'll want to avoid shapes that have a short vertical height. This dimension is called the B Measurement. ​As a guide, try to select a shape that has a B Measurement of at least 30 mm. This should allow enough room for the distance, intermediate and reading portion of your lens.

eyewear frame measurements

​If you elect to go with Single Vision Reading lenses then you can go as small as you like; just be aware that the smaller you go the more aware of the frame you will be. This can annoy some people.


Lens Options You Want

Now that you've gained a better understanding of your prescription, I suggest thinking about the lens options that you want on your new glasses.

Some options to consider:

  • Transitions

  • Blue Light Filtering

  • Premium AR Coating (i.e. Crizal, Zeiss, Shamir)

  • Polarized

  • Mirror Coating

  • Hi-Index Materials

  • Progressive type and manufacturer

There are plenty of generic lens options out there but long time prescription glasses wearers have come to enjoy the quality of specific brands. Take Photochromic lenses for example. Just about everyone offers light sensitive lenses but not everyone offer the Transitions brand. Generic versions of this technology take longer to darker, longer to go back to clear and they often have a noticeable tint on the lens when it's supposed to be completely clear.

Another example could be premium sunglass lens options such as mirror coatings and backside Anti-Reflective coatings. These features are not available on all online stores.

It's unfortunate that consumers don't have an easy way to compare the quality of lens options available online. They are not all created equal even if they use terms like "premium". This is what makes it so difficult when doing comparative shopping. It's not like going out and trying the "premium beef" hamburger from a fast food chain. The quality of your glasses may not be determined until you've had a chance to wear them for a few months.

That's why many of my patients elect to go with brands that they are familiar with. Crizal, Transitions, Varilux and Zeiss have an established reputation for quality which consumers trust.

Again, not everyone cares about specific brands and the generic offerings on many online sites seem to be good enough for the average wearer. But if you want specific products be sure to check for that before you spend an hour browsing through frame options.

Related Article: Standard vs. Premium Anti-Reflective Coatings


Now, The Frame Search Begins!

Selecting a frame can be overwhelming for some people. Whether you shop online or in a store you'll likely be confronted with a seemingly never ending amount of options. Have no fear; our guide will make it easy to understand the variety of frames types so you can select the best frame for you.

As you scroll through the options, keep in mind that frames are typically defined by the primary material used on the frame front.

Metal Frame

Metal frames, aka wire frames, are made in materials such as Stainless Steel, Surgical Steel, Titanium, Beta Titanium, Aluminum, Gold and other metal combinations. Here are some common characteristics of metal frames:

  • Adjustable Nosepads

  • Thin Profile

  • Light Weight (Depending on the material)

Modern optical around gold


If you're looking for a low profile, lightweight frame then metal is a good option. Don't write them off because of the nosepads, when adjusted properly, nosepads are your best friend. They keep frames from slipping down your nose, they allow the frames to sit further from your face so your eyelashes don't touch and they lift the glasses so you have more lens to look through.

Some manufacturers get real creative with metal so there is no shortage of unique styles and color. Add the great selection of available metals and you'll be sure to find something to suit your style.


I'll be honest, nosepads aren't for everyone. Because they are adjustable that means they can get out of adjustment. When this happens the nosepads can become uncomfortable and even hurt. If you're hard on glasses, you'll need to get them adjusted more often than you'd like.

Nickel is a common metal used in "cheap" metal frames and data shows that 10-20% of people are allergic to it.

Plastic Frames

Plastic frames are made of materials such as Acetate, Ultra Dense Acetate, Optyl, Ultem, SPX, Nylon, Polycarbonate and more. There is an almost uncountable amount of color combinations and styles. Here are a few common characteristics of plastic frames:

  • Most do not have nosepads

  • More color options than metal

  • Bold, low profile and everything in between


There are many advantages to plastic frames and I like to use "low maintenance" to summarize them. They typically don't have nosepads, they don't have as many weak points as metal frames and if you get a good quality plastic they will hold their adjustment for months or years.​


Since there are usually no nosepads, the way the bridge fits at the beginning will be the way it fits for the life of the frame, unless you modify the bridge by adding nosepads. This will void any manufacturer's warranty so only do this when you have no other choice.

If a plastic bridge is too wide they will slip and the full weight of the frame is placed on the top of the wearer's bridge. This can be quite uncomfortable.

Some low quality plastics lose their adjustment quite easily. The whole "low maintenance" thing will not apply to poorly made plastic frames.


Rimless frames, aka 3-Piece frames, are commonly found in materials such as Titanium, Beta-Titanium, Steel and in some cases, flexible plastics. Here are a few characteristics of rimless frames:

  • Almost always have nosepads

  • Can be ultra light-weight

  • Lens shapes can be customized


The most common types of rimless frames focus on being light-weight and low profile. Frames made with Titanium or Beta Titanium are extremely light and it's not uncommon for them to last over 2-3 years without breaking.

The best rimless frames are made by companies that are rimless specialist. By this I mean they focus most of their resources on developing mounting methods, frame materials and hinge designs that are often patented to that one company.


The best rimless glasses tend to cost upwards of $400-$500. This can be more than some people are willing to spend. Good quality rimless glasses should be considered a long term investment.

Almost all rimless frames are mounted via drilling through the lenses. These drill points can eventually lead to stress crack or even a broken lens.

Half Rimless

There are a few variations of half-rim frames but the most common version has a frame across the top of the lenses and a thin nylon string beneath the lens. This type of frame requires the lenses to be grooved in order to accommodate the nylon string. Here are a few common characteristics of half-rim frames:

  • Almost always come with nosepads

  • Most are made out of metal

  • Lenses are mounted through a groove instead of a typical bevel

rayban 6589 gold


Half-rim frames can be a happy medium for people that want a low-profile and lightweight frame without having to go complete rimless. When lenses are fitted properly, you can expect very little maintenance because there are no screws needed to keep the lenses in place.


Half-rim frames can be a little tricky to adjust for the novice optician because they require a different approach. Often times the lenses need to be removed in order to bend the frame into alignment and DIYers may struggle on their own.

Because the lenses require a groove, a chip resistant lens material may be required and not optional.


3 Frame Fitting Tips

Some people don't have a hard time finding a frame that they like but they do have difficulty finding a frame that they like and that fits well. Here are the 3 areas of a frame you need to pay attention to for proper fit.


The bridge, aka DBL (Distance Between Lenses), is the part of the frame most responsible for supporting the frame and keeping it in place. ​If the frame has adjustable nosepads then the immediate fit isn't as critical since they can always be made narrower or wider.

If there are no adjustable nosepads then it becomes really important to get the fit right from the beginning. Use this as a guide:​

  • Look for a "saddle" fit: An even distribution of the frames bridge across the bridge of your nose. (See Ex.1 Image)

  • Gaps/spaces on the sides mean too much weight is being placed at the top of the nose. This can be uncomfortable since all the weight will be concentrated there.

  • A small amount of space at the top of the bridge is ok.

Ex.1: A proper fit for a frame with no nosepads.

Frame Width

The frame width is almost just as important as the bridge fit but there is a little more room to work with here. The key is to minimize the amount of space between your temple and the arms of the frame. (The technical name for the "arms" is also Temples)

Too much space in this area and the frames may be too wide to fit securely and too little space may place undesired pressure that can lead to discomfort. If you can fit your index finger between the frame and your temples the glasses are most likely too wide.

There are exceptions to this rule since there are some people, in particular young children, that have a diamond shaped head which means the head is a bit wider above the ear then the temple area. In these situations you'll want to go with a frame that has spring hinge or flexible temples. This will allow a slightly smaller frame to fit without putting too much pressure on the wearers temples.

The ideal frame width places the wearers eyes near the center of the lenses. (See image below)

Temple Length/Type

The temple length is often overlooked but you shouldn't ignore this part of the frame. If the temple is too short then it can't be bent down behind the ears properly in order to keep the frames from slipping down and moving around.

Most adult frames should have a temple length between 140-150mm. When bent, the end of the temple should reach about half way down the back of the ear.

There are some temple styles that are not bendable, rather, they are straight and bowed. Instead of hooking behind the ear, this style will feel like it hugs your head. This is a common temple style for sports brands.

One isn't really "better" than the other, it comes down to personal preference. Though it is more common for people to prefer the type you can bend behind the ear (aka skull temples); It tends to have less constant pressure.


Happy Shopping

I hope that you find this guide to be useful. These are just some of the parameters a good optician needs to process each time they fit a set of glasses. Shopping for glasses online is an option many will consider, if they haven't already ventured to try the experience.

#glasses #prescriptionglasses #Optician #website #crizal #antireflective #eyewear

bottom of page