Need help with my contacts?

I was going to order some online but the ones I have aren't right. I was curious. The ones I wanted have a BC of 8.4 and my BC is 8.5, also the DIA is 14.2 for mine and the ones they have is 14. Does it matter if these numbers aren't exact or does it? I would really like this type and brand but can get everything exact. Also what is the DIA and BC for contacts.