Pretty, and pretty big comb.... what breed is that? Do you have others from the same hatching... how does "he" look next to the others, compared with the others.
For me, it's pretty much a guess.. but, I have to look at the comb, the legs, the size and the tail, compared with "brothers and sisters".... some of my neighbors can tell by the 'peep'.. the sound of their voice and all.. I can't yet.
Although it does seem as if the ones that peep the most, are the most noisy (when young) are always cockerels. ("Mama's boys")
Knowing I know little.. the comb is large.. and getting pretty red.. . I am guessing cockerel... my guess is, "it's a boy". But a whole body look and in the group pics would help, for me.
I hope "it" turns out to be what you want.. best of luck.