The sex of most breeds of chicken cannot be determined at hatching. Usually by 6 to 8 weeks of age, the combs and wattles of male chicks will be larger and redder than those of females, as in the photo of sablepoot chicks below (male on the left and females on the right). Often the legs of males are chunkier too. Male chicks may start to crow from around 12 weeks old but they can start much later. Sometimes you can see differences in behaviour between males and females. Male chicks can strut from an early age with their chests out and head in the air. Some breeds are notoriously difficult to sex, e.g. silkies, in which case you may not be able to determine their sex until they are adults and they either start to crow or lay eggs!
Feather Sexing
According to some, you can feather sex a chicken within the first 3 days. A girl chicken will have 2 different lengths of wing feathers and a boy chicken will have wing feathers that are all the same length.
Tail Sexing
The chicks who develop tail feathers first are female.
