The chicken breeds recognized by the American Poultry Association are listed in the American Standard of Perfection. They are categorized into classes: standard-sized breeds are grouped by type or by place of origin, while bantam breeds are classified according to type or physical characteristics.
The large breeds are divided into six classes – American, Asiatic, Continental, English, Mediterranean, and All Other Standard Breeds – largely according to their place of origin.
The American Class contains thirteen breeds which originated in Canada or the United States.[1]: 11 All are heavy breeds, and most lay brown eggs;[1]: 11 most are cold-hardy:[2]
These three breeds originate in China; they are large, feather legged, and lay brown eggs:[1]: 21
This group consists of eleven breeds from Belgium, France, Germany, and the Netherlands. They are mostly sprightly birds, the Faverolles being an exception:[1]: 70
This class consists of five breeds from the United Kingdom and one from Australia:[3]
These breeds originating in Italy and Spain have white earlobes and tend to be productive layers of white eggs. In general they are flighty, and exceptional free-range birds, with both evasion and foraging skills:[1]: 178
Other breeds are grouped in this class, which has three subclasses: Game, Oriental, and Miscellaneous. The Game subclass includes the non-oriental game birds, the Oriental subclass includes mainly birds from Asia; the Cubalaya, however, is from Cuba. The Miscellaneous subclass holds the remaining breeds.[3]
Bantams are grouped according to type or physical appearance into six classes:[3]
This class consists solely of the Modern Game bantam.[1][3]
The Game class includes the remaining game bantams:[1][3]
This class contains all the bantam breeds with a single comb, excluding the game bantams:[1][3]
This class groups breeds with both a rose comb and featherless legs:[1]
The breeds of this class have feathering on their legs and feet:[1][3]
This class includes all of the breeds that do not fall into any of the other classes:[1][3]