How Big Will My Puppy Get?
Predict your puppy's adult weight and growth timeline from current age and weight. By breed size category.
How Puppy Growth Works
Puppies do not grow at a constant rate. Growth is fastest in the first 4-6 months, then gradually slows. Small breeds reach adult weight by 9-12 months. Medium breeds by 12-15 months. Large breeds by 15-18 months. Giant breeds (Great Danes, Mastiffs) may not reach full adult weight until 18-24 months.
Common Growth Prediction Methods
The simplest rule of thumb: double the weight at 4 months for medium breeds. For large breeds, double the weight at 5 months. For small breeds, double at 3 months. This calculator uses a more precise growth curve model that accounts for the non-linear nature of puppy growth.
A puppy's paw size is one of the best visual predictors of adult size. Disproportionately large paws on a young puppy almost always indicate a large adult dog. The puppy will "grow into" those paws over the next 12-18 months.
