Puppy Weight Calculator: Adult Dog Size
This puppy weight calculator estimates how much your dog will weigh when fully grown. Enter your puppy's age in weeks, its current weight in pounds and its expected adult size (toy, small, medium, large or giant). Small breeds finish growing by about 10 to 12 months, while giant breeds keep growing until 18 to 24 months, so the calculator uses a growth curve for each size class instead of one rule. You get an estimated adult weight range and a month-by-month chart of expected weights.
Puppy Weight Calculator
Estimate how big your puppy will get from its age, current weight and breed size.
How to use the Puppy Weight Calculator
- Enter your puppy's age in weeks.
- Enter its current weight in pounds.
- Choose the expected adult size class.
- Read the estimated adult weight and growth chart.
Puppy weight estimate
Adult weight ≈ current weight ÷ (typical share of adult weight reached at this age for the size class)
Features
- Five breed size classes
- Adult weight estimate and range
- Growth chart by age
- Pounds and kilograms
Frequently asked questions
How can I tell how big my puppy will get?
Compare its current weight with the typical share of adult weight reached at its age. A medium puppy at 16 weeks usually weighs about 40% of its adult weight, so a 14 lb puppy may reach about 35 lb.
At what age is a puppy half its adult weight?
Small breeds reach half their adult weight at about 3 to 4 months, medium breeds at about 4 to 5 months, and large and giant breeds at about 5 to 7 months.
When do dogs stop growing?
Toy and small dogs stop at about 9 to 12 months, medium at about 12 to 15 months, large at 15 to 18 months and giant breeds at 18 to 24 months.
Do paw size and parents predict size?
The parents' weight is the best guide. Big paws can hint at a larger dog but are not reliable on their own.
How accurate is this estimate?
It is a rough guide. Mixed breeds, diet and genetics cause real dogs to differ by 10% to 20%. Ask your veterinarian about your puppy's growth.