I've got a few Jags, And sometimes they fool me. But I'm leaning to male.
Body shape, Heads shape, Slightly swept back dorsal fin, All the belly spots
seem as dark as the back spots. And the large side spots don't always go away.
But when he hits about 6"s you'll know for sure.
I'd normally say male.. But females SOMETIMES have great male markings. My female looked just like that. If it had even a single spot on its gill plate then I would be convinced it was male. But at this size the lines from her eye to the end of the gill plate would begin breaking up if it was male. It's going to be a stunning female though. Keep us updated, please.
Also those spots would be completely black, with no brownish outline at all