How do puppies, dogs grow? At what rate? I am trying to get a sense of how big my dog will be. Is there a way to know?

My puppy is 7 months now and she has more than doubled in weight and, it seems, somehow, quadrupled in size since I got her at 2 months. She had this amazing growth spurt in those months but seems to have slowed down in her growth in that last month or so. Is that common? Is that the way dogs grow? How can I tell how big she will eventually get? She’s a mixed breed.