Predict how big your puppy will be as an adult. Enter your puppy's current age and weight to estimate their full-grown size using veterinary growth formulas.
Breed Size
Puppy Details
Predicted Adult Weight
Breed Size: Medium
Growth Rate: —
Weight Range: —
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The puppy weight calculator predicts your puppy's adult weight based on their current age, current weight, and breed size category. Smaller breeds reach adult size faster (around 9–12 months), while large and giant breeds may continue growing until 18–24 months. This calculator uses standard veterinary growth curve formulas to estimate your puppy's full-grown weight.
Puppy weight predictions are estimates based on average growth curves. Actual adult weight can vary by 10–20% due to genetics, diet, health, spay/neuter timing, and individual variation. Mixed breed puppies are harder to predict than purebreds.
Toy and small breeds typically reach adult size by 9–12 months. Medium breeds by 12–15 months. Large breeds by 15–18 months. Giant breeds may continue growing until 18–24 months. Most puppies reach about 60% of their adult weight by 4 months.
The best predictors are: breed (or parent sizes for mixed breeds), paw size (large paws often indicate a large adult), and current weight relative to age. A common rule of thumb is to double the weight at 4 months for medium breeds, or at 5 months for large breeds.