Puppy Weight Calculator

Estimate your puppy's adult weight based on their current age and weight. Uses breed-size-adjusted formulas for 2026.

Enter puppy details

How It Works

This calculator uses the growth-rate formula: it takes your puppy's current weight, divides by their age in weeks, then projects to 52 weeks (1 year). A size-category multiplier adjusts for the fact that larger breeds continue growing well past their first birthday.

For Best Results

Use this calculator when your puppy is between 12 and 20 weeks old for the most accurate estimate. Very young puppies (under 8 weeks) or older puppies (over 6 months) may give less accurate results.

Small breedsReach adult weight by 10–12 months
Medium breedsReach adult weight by 12–15 months
Large breedsReach adult weight by 15–18 months
Giant breedsReach adult weight by 18–24 months

Frequently Asked Questions

This calculator provides an estimate based on growth rate formulas. Accuracy is best when used between 12-20 weeks of age. Individual genetics, diet, and health can cause actual adult weight to vary.
The most accurate estimates come from puppies between 12-20 weeks old. Very young puppies (under 8 weeks) or older dogs (over 6 months) may give less reliable predictions.
Yes, male dogs are typically 10-15% heavier than females of the same breed at maturity. Our calculator provides an average estimate — males may be slightly above and females slightly below.