Originally Posted by Cup of Tea
I'm still kind of confused on IV breeding.

Say you have two parents of the same species with these IV spreads: 31/31/x/31/31/31 holding a destiny knot and x/x/31/x/x/x. What is the chance of getting a flawless offspring? Also, how do I calculate IV's in X and Y? I've tried to figure it out since Gen 4, and never have been able to, even using a calculator. I never got accurate answers.
With those IV Spreads and Destiny Knot, then the probability is (1/2)*(1/2)*(1/2)*(1/2)*(1/2)*(1/32)*6C5=3/512
Destiny Knot guarantees the passing of 5 IVs from the parents. For each stat, one out of each parent has a Perfect IV. Five out of each 6 stats will be gained from the parent and the last IV will be randomly generated from 0-31.

To find out which perfect IVs you have, go to Killoude City's PC and talk to the NPC in purple and he will look at your Pokemon's IVs. If he says "this stat can't be beat", then you have a Perfect IV in that stat. If you want to know exact IVs for the remaining stats, I have no idea.