How to tell what your vision is from your contact perscription?

Question

If my contacts are -7 and glasses -7.25, what is my vision? (100/20 for example)

Answer 1

To tell your vision, you would have to look at an eye chart.

Answer 2

There is no way to tell your visual acuity by your prescription alone, however you are very myopic meaning that when you are looking at something it focuses in front of the retina, your visual acuity without correction is probably around 20/100 or maybe even worse. Next time you go to your ophthalmologist ask what your visual acuity is without correction, or you could even call the office and a tech could tell you over the phone.