I've been told you can't tell until they are feathered out. When I ordered a frizzle cochin from mypetchicken she made sure I understood that it may or may not frizzle and that I won't know which it is for a while. Right now she's 26 days old and I don't see any signs of frizzling, but who knows what may happen as she feathers more. Having said that, I am far from the authority as this is my first time with a potential frizzle.