The base stats are converted into real stats by the following formula at Level 100:

**(Base Stat *** 2) + 5*

Unless HP, which is: (Base Stat 2) + 110

So if you have a Pokemon with 170 Base Attack, you would plug it into the formula as such:

**(170*2) + 5

340 + 5

345 = n** (for later)

So it would have a stat of 345. However, this is with 0 IVs. This stat could raise by as much as 31 with a perfect IV. So you could have a stat anywhere between 345-376 now.

However, EVs come into play as well. Every **4** EVs on a Pokemon raise the stats by **1,** meaning **252** EVs raise the stat by **63.** Also, natures raise a random stat by 10% and lower a random stat by 10%. There are also 5 natures that raise or lower no stats. They are Serious, Hardy, Docile, Bashful and Quirky. Source.

So, for example, say you have a Kyruem-Black with 27 IVs in Attack, a Quirky nature, and 184 EVs in Attack. Remember the variable "n" earlier? This saves us work, as we know Kyruem-B's minimum stat.

The equation we would use is:

**n + 27 + (184 / 4)**

n + 27 + 46

n + 73 *(Since n = 345,)*

**345 + 73**

418

Therefore, your Kyruem-Black would have an attack stat of 418.

*Source: Here*