🐶 Puppy Weight Calculator
Predict adult weight by dividing your puppy's current weight by the fraction of its adult size it has reached so far — which depends on age and breed size.
10 kg
Estimated adult weight
50%
Of adult weight reached so far
The estimate divides your puppy\'s current weight by the fraction of adult weight it has typically reached by this age for its size class. Small breeds finish growing by about 10–12 months; large and giant breeds keep growing to 18–24 months. This is an approximation based on breed-size growth curves — real adult size depends on breed, genetics and nutrition, so treat it as a guide, and ask your vet about healthy growth. 🔒 In your browser.
How the puppy weight calculator works
Puppies of different sizes grow at different rates: small breeds reach most of their adult weight quickly, while large and giant breeds keep growing for up to two years. The calculator looks up the percentage of adult weight a puppy of your chosen size class has typically reached by its current age, then divides the current weight by that fraction to estimate the adult weight. Pick the size class that matches the expected adult size (or the breed).
This is an approximation from published breed-size growth curves — real adult size varies with breed, genetics, sex, spay/neuter timing and nutrition, so treat the number as a guide, not a guarantee. Estimates are most reliable from around 12–16 weeks; very young puppies (under 8 weeks) give rougher predictions. For a mixed breed, choose the size class of the larger parent if unsure, and ask your vet whether your puppy is growing at a healthy rate.
Frequently asked questions
How big will my puppy get?
Enter its current age, current weight and size class. The calculator estimates the adult weight by scaling up from the fraction of adult size a puppy that age has usually reached. It's an estimate — breed and genetics cause real variation.
At what age do puppies stop growing?
Small breeds finish at about 10–12 months, medium breeds around 12 months, and large and giant breeds keep filling out until 18–24 months. That's why the calculator uses size class to scale the prediction.
How accurate is a puppy weight prediction?
It's a reasonable ballpark, most reliable from 12–16 weeks onward, but not exact — individual genetics, sex and nutrition shift the outcome. Use it as a planning guide for crates, food and expectations, not a precise figure.
What size class should I pick for a mixed breed?
Estimate from the parents if you know them, choosing the larger parent's class when unsure. If you don't know the parents, your vet can often estimate adult size from paws, frame and growth so far.