Not automatically. Them sparring doesn't either. Sexing chicks is as much art as science if not more. Experience can help. There are several different signs that a chick may be a boy or a girl. Some of those kick in around 5 weeks but I remember one that I thought was a girl until he was 4 months old. Occasionally I can tell at hatch that one is a boy, mainly by posture, body shape and sometimes attitude but that is not normal. It is generally harder for me to say that one is definitely a girl than to say one is definitely a boy but sometimes there is no doubt.
You can try posting photos at five weeks, we might be able to tell by then. I'd suggest two photos of each chick. One shot showing the head so we can see the comb and wattles. Size of the comb, the presence of wattles, and especially the color are clues. A bright red at that age is a strong indicator of a boy.
The second photo should show legs, posture, and profile. Heavy legs indicate a boy. A boy would have an upright posture. And just body shape can help. When they get older saddle and hackle feathers can help, boys' are sharp while girls' are rounded, but 5 weeks is too early for that.
As for attitude, the boys tend to be bold and brave. They come out in front to check you out while the girls tend to hang in the background. That's a danger to you. The boys appear friendly and have personality, you often fall in love with them. They are your favorites. It's a trap, don't fall for it.
Sometimes we can reach agreement even at 5 weeks that one chick is definitely of a certain sex. Sometimes even a month later we can't all agree. Like I said, more of an art than a science.
