You might grow until 21 if you're a late bloomer (didn't start puberty until 14 after). 23-25 is extremely rare. Vast majority of men stop growing 18-19. Assuming you're not a late bloomer, HGH only works if you use it mid-puberty at the latest, and even then it only makes you reach your genetic height potential faster, it won't make you surpass your genetic cap. Most of your growth will be finished by the time you turn 16-17. You might grow one more inch after that. Glucosamine can make you retain morning height. Stretching and hanging/inversion will add 1 cm to your height- temporarily, that is. Posture correction can increase your height, only if you have a pre-existing posture problem though. And then there's shoe lifts and LL surgery which everyone already knows about. Everything else is cope.