Adult barred rock roosters crow, have larger wattles, combs, bodies and spurs, have pointed hackle feathers and saddle feathers, and the male comb develops earlier than on females. Hens have a comb that flops to the side and round or oval-shaped hackle feathers.
It is very difficult to determine the gender of barred rock chicks. Eighty percent of the time, barred rock chicks that have purebred parents are born with a gender identifying white dot on the tops of their heads. This dot is larger in males and narrower in females. Barred rocks hens that are mated with brown-headed roosters produce male chicks that have a yellow dot on the crown of their heads and yellow beaks, shanks and toes. Female chicks are all black and have darker colored beaks, shanks and toes. If a barred rock hen is mated with any Mediterranean breed of rooster, then the genders of the resulting offspring can be determined using their wing feathers. Mediterranean breeds include Minorcan, leghorn, Spanish, Andalusian, Anconan and buttercup.
At birth, females have fully developed wing feathers, while males have no wing feathers. Females also shows signs of tail growth after a week, whereas males do not. However, the feathering on males and females is uniform after a week and a half.