Help with glasses/contacts prescriptions?

Question

If a glasses prescription is -300, what is the contact prescription? Then, does -3.75 contact prescription mean better eyes or worse eyes than the -300?

Answer 1

My eye doctor explained to me that eyeglass and contact lens prescriptions should be different. The contact lens is directly on the eye rather than separate from it as the eyeglass lens is.

My personal experience with contact lens vs. eyeglass lens prescriptions is that my eyeglass prescription is stronger than my contact lens prescription. (For the record, I'm nearsighted--my eyeglass prescription is similar to yours--and have an astigmatism.)

I'd be surprised if the contact lens prescription is stronger than your current eyeglass prescription. However, if you just had an eye exam and your -3.00 prescription was from your previous glasses and the -3.75 prescription is from your most recent exam, that means your eyes have changed and you need a stronger prescription.

Ask your eye doctor about the difference in the prescriptions; s/he will be glad to explain it to you.

Answer 2

You can not convert a perscription for glasses to a perscription for contacts. A -3.75 is worse than a -3.00. The farther away from 0 it is the higher the prescription.

Answer 3

If the glasses prescription is just -3.00 sphere , with no astigmatism...then the contacts should be the same power.

Converting the power, making the contact weaker, doesn't start until - 4.00...or if there is any astigmatism correction to be combined into it.

A glasses Rx can be converted to a contact Rx, but not the other way around , for the first responders info.