A dog’s development timeline varies based on its breed, and there is no exact moment when a puppy can be deemed an adult. The transition typically occurs within a range of time intervals:
For small breeds like the Pug, Toy Poodle, and Dachshund, the shift happens around 9 to 12 months of age. In medium-sized breeds such as the Border Collie, Pitbull, and English Bulldog, the transition occurs between 12 to 15 months. Large breeds like the German Shepherd, Labrador, and Boxer reach adulthood between 15 to 18 months, while giant breeds such as the Saint Bernard or Great Dane complete their development between 18 to 24 months of age.