Or 1 in 10 to 1 in 20 or so if it's gambled at Kadala or upgraded from rares with the cube, depending on slot (this drastically reduces the item pool so makes it much more likely you get two of the same item). Which is 1 in a few hundred if it's a random drop. You just need to know the probability that two drops are the same item. Since you are conditioning on both items being primal. If you asking what the chances of the first two primal you find being the same item, the chance of the item being primal doesn't matter. OP, you can sort of ignore the probability of an item being primal in this calculation. So it's probably somewhere in the ballpark of 1 in 300. It depends a bit on class (different classes have different numbers of items in their drop tables) but I think it's a few hundred items for each class. Which is 1/365.Īnd funnily enough, the probability of two items being the same is similar here. This is more like the probability that exactly two people have the same birthday. That would be similar to the birthday paradox.

OP oesn't have 20-30 primal items and wants to know the chances two of them are the same.

He would have to have more primal items for this to apply.

Diablo 3 season 11 primal ancients