According to The Daily Puppy, smaller dogs tend to stop growing at around one year of age. Larger breeds stop growing anywhere from one year to three years of age.
All dogs go through a growth spurt shortly after birth. While smaller dog breeds tend to grow quickly during the first year of life, larger breeds stop growing quickly after their initial growth spurt. Instead, larger dog breeds often grow to their full height first and then gradually build muscle and mass over a period of years. According to Paw Posse, dog owners can gauge how much growth a dog has left by the size of its paws. If a dog's paws are on the large side even after a growth spurt, it is not fully grown.