"I bought the size 3/4 for my son that is almost 2 1/2. He wears 2/3T tops and 24m/2T bottoms. The costume fits perfectly. I also purchased the larger size hoping it could last longer for dress up and it was huge on him, so I am returning it. My only complaint is that the poor design of the hood makes it hard to get on and it's tight. The wings are a great addition, skip the gloves."