The standard did Black Dogs does say 22-24 is ideal for bitches and 24-26 for dogs. It gives a good bit of leeway either way though. Then there's out of standard dogs too. The actual size of them can really range from about 18" for the smallest under sized bitches to 28"+ for the biggest oversized males. So they can range from mediumish to pretty large. Roust at 6 months is almost as big as Whim!