What is a contact lens base curve, and how does it affect you?

When buying contact lenses, many of us only know our power/grade, and then we buy a box of 1-Day Acuvue Moist because that's what Susan from Accounting recommended yesterday during lunch.

The truth is that contact lens prescriptions and spectacle prescriptions are not the same, and one of the reasons is because contact lens prescriptions contain base curve and diameter values, which affect how the contact lens sits on your eye.

Click on any of the buttons below to see what happens when you wear contact lenses with the wrong base curve.

Too Small Just right Too Big

Too Tight

A base curve that is too small can cause the contact lens to sit too tightly on the cornea. Mild symptoms might include discomfort or dry/itchy/red eyes, but it can also block off oxygen supply or even damage the cornea. That's why some people claim that contact lenses make their eyes feel dry or turn red, sometimes it's just because they are wearing a wrong base curve.

Just right!

A base curve that is just right allows the contact lens to sit properly and work as it should. This means comfortable eyes and great vision! Contact lenses nowadays are softer and more pliable so sometimes you might not even notice your base curve is wrong, but we recommend to always have an eye doctor prescribe your contact lenses suitable for you before buying from us.

Too Loose

A base curve that is too big will cause the contact lens to not sit properly on the cornea. While less medically dangerous than wearing an overly-small base curve, it can still cause annoyance from the contact lens shifting around or poor vision. You may also notice your contact lenses get dislodged or fall off easily, especially when you blink.

We hope that gives you a better insight on why we always emphasize the need to ask an eye doctor which contact lenses are suitable for your eyes before purchasing them from us. We would love to have your business, but your safety when wearing contact lenses is even more important to us. If you already have your prescription, well done! You can learn how to read it here or head over to our shop to start shopping. If not, you know what to do: find an optician!

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The Contacts Asia family


Jacob Lewis

Jacob Lewis

Are you still in business?
I found a few errors on your site.
Would you like me to send over a screenshot of those errors?

(714) 500-7363

Amy Saunders

Amy Saunders

After spending a year wearing glasses, my cousin has decided to try something else because he doesn’t feel comfortable with it. Perhaps he could seek some advice from an expert before applying any product soon after. In the meantime, thanks for telling us about how our contact lens could actually stay still if it has the right dimension of base curve. https://bestvieweyecare.com/

Mia Arlona

Mia Arlona

Anyone here?



That is really a good tip especially to those fresh to the blogging simple but very accurate info many thanks for sharing this one a must read post very nice article.HOW DO CONTACT LENSES WORK

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