News

How to Convert Glasses Prescription to Contacts


Have you been wearing glasses for ages and looking for a change? Maybe you want to ditch the specs and try something new – like contact lenses. They’re an amazing product. Not only can they help you see without a glasses frame getting in the way, but there’s a large selection of colored contacts that can add a bit of style to your daily look.

But, the big question is: can you convert a glasses prescription to a contact lens prescription? Luckily for you, the answer is yes! Since both contact lenses and glasses work the same way, by correcting refractive errors such as myopia, hyperopia, astigmatism, and presbyopia. Below, we’re going to discuss the differences and how to convert glasses prescription to contacts.

Are glasses and contact lens prescriptions the same?

A common misconception that many people believe is that a glasses prescription is the same as a contact lens prescription. In fact, there are quite a few differences. For example, glasses don’t sit directly on your eyes like contacts do. They are about an inch or two away. This means that when you get your eyes tested, two different tests and measurements need to be taken. One for glasses, and one for contact lenses.

Similarly, depending on the type of refractive error you have, the strength of the lens on your glasses and contacts may be different from each other. Therefore, when you want to convert your glasses prescription to contact lenses, it may not be as simple as you believe. There are different measurements and parameters that need to be taken.

Glasses and contact lens differences

If you are lucky enough to be someone who has both glasses and contact lenses, then you may notice some other measurement differences when examining your prescription. For example, commonly there is a cylinder and axis value on a glasses prescription but not for a pair of contact lenses. The only times you may find a contact lens prescription with an axis and cylinder is if it’s a toric lens or multifocal lens.

Since contact lenses are much more delicate and need to fit the eye, there are certain specifications that they have that a glasses prescription will not. With a contact lens prescription, you’ll be able to see the base curve and the diameter The base curve is simply the curvature of the lens and is on the shape of your eye. The diameter specifies the overall size of the lens.

Vertex conversion chart for contact lenses

So, with so many differences, how can you possibly find a way to change your glasses into a pair of contact lenses without having to go through excess testing? That’s when a vertex conversion chart for contact lenses comes in. They are extremely useful tools that all eye doctors use when determining how to convert glasses prescription to contacts.

This chart includes different figures for you to compare. The first thing you do is finding out your glasses prescription figures. These are then ‘back vertexed’ using the chart to turn them into a figure that allows you to find the correct contact lenses for you.


How vertex conversion charts work

Vertex conversion charts are pretty simple to use. You just have to know where to look and understand what the columns mean. The ‘glasses lens power’ column refers to the power on your current glasses prescription. If this figure is negative, then you’ll be converted to the figure on the left of this column. If the figure is positive, then your converted figure is on the right.

However, many vertex conversion charts only start at glasses prescriptions of +/-4.00D. This doesn’t take into account any powers lower than this figure. This is because the converted power is not much different from your original power. You can get away with using the same power as your glasses prescription when converting to a contact lens prescription. The one exception for this case, however, is when you have an astigmatism.  

Are you ready for prescription contact lenses?

You now have all the answers for how to convert glasses prescription to contact lens. Although the two prescriptions are different, and you cannot use the same figure, there is still a way. A vertex conversion chart has become a game changer for many people who want to change to contact lenses. Instead of going through the long process of extra eye tests when you first got your glasses, you can use a simple chart to discover your new contact lens prescription power.

Once you use the chart, the power is in your hands. You can opt for simple, clear contact lenses, or you can switch things up and purchase some colored contacts. They can add something extra to any look, whether it’s your day-to-day or going out. You can check out the amazing range on Eyecandys today and find your new favorite pair of prescription contact lenses.


Trending This Week

You have successfully subscribed!

This email has been registered