Most people don't really talk about this.
How bad are your eyes?
How strong is your prescription/
We use 20/xxx to describe our vision. With my contact lenses, I see 20/20 - perfectly. Without them, I'm legally blind - beyond 20/400.
If you asked me the actual prescription for my contact lenses, I could tell you the "diopters" because it's on the lens case. I have no idea what my glasses prescription is - I just give it to the optician.
Eyeglass prescription - Wikipedia, the free encyclopedia
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