Puppy Weight Calculator
Enter your puppy's age and weight today. We'll estimate the adult weight from typical growth curves for its size.
How the calculation works
Puppies follow a growth curve that depends mostly on adult size. Small breeds reach about half their adult weight around 3 months and finish growing at 9 to 12 months. Giant breeds are only about a quarter grown at 4 months and keep filling out until 18 to 24 months. The calculator looks up what share of adult weight a typical puppy of that size has reached at its age, then divides:
adult weight ≈ current weight ÷ share of adult weight at this age
| Age | Small | Medium | Large | Giant |
|---|---|---|---|---|
| 2 months | 30% | 22% | 17% | 12% |
| 3 months | 45% | 35% | 27% | 20% |
| 4 months | 60% | 47% | 37% | 28% |
| 6 months | 82% | 68% | 55% | 44% |
| 9 months | 96% | 88% | 76% | 64% |
| 12 months | 100% | 97% | 89% | 79% |
| 18 months | 100% | 100% | 100% | 96% |
These are typical values. Individual puppies, mixed breeds and dogs from show versus working lines can differ by 15% or more.
Other quick rules
- Small breeds: double the weight at 3 months, or weight at 6 weeks × 4.
- Large breeds: double the weight at 6 months.
- Paws: big paws hint at a big dog, but they're an unreliable guide.
Frequently asked questions
When do puppies stop growing?
Small breeds stop around 9 to 12 months, medium breeds around 12 to 15, large breeds 15 to 18 and giant breeds up to 2 years.
Should I feed a large-breed puppy food?
Yes, if your puppy will be over about 50 lb as an adult. Large-breed puppy foods control calcium and calories to slow growth slightly, which lowers the risk of joint problems.