She won't have stopped growing - just slowed down so it's no longer patently obvious. She's
probably within a couple of inches of her final height - but she won't reach that until about 14-16 months old or so.
Anyway - a female boxer is supposed to be between 21-23 inches tall, measured to the withers. So if your girl is at least 19 inches tall at the moment, then she's going to end up perfectly correct. There are a lot of oversized dogs out there though, so don't just compare her to others, measure and see. Very likely it is your dog who's going to end up a correct height and the others are oversized for their breed
