The average person cannot because sex is very difficult to tell in chicks but, their are actual ‘chicken sexers’ that specialize in this. The way to tell is the feathers grow different in each sex. While females have different feather lengths, males lengths are even. Also, on the bird’s rear males will have a pimple like bump, while females do not. Like I said either way it is hard to tell and the average person is probably better off waiting until they mature and they start to take on outward female and male characteristics.