PuppyCalcs

Puppy weight calculator

Enter your puppy's age and weight to see how big it will get. Built from the weigh-ins of more than 1.4 million dogs.

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How it works

  1. Pick your puppy's breed, or leave it blank for a mixed breed.
  2. Enter age and today's weight. Weigh at the same time of day for consistent numbers.
  3. The calculator compares your puppy with how dogs of its size typically grow, then shows the likely adult weight, a range, and the projected weight at later ages.

How accurate is it?

We checked the method on dogs it hadn't been fitted to: the typical miss was about 11% of adult weight, and around 4 in 5 dogs ended inside the range. Younger puppies are harder to call.

Puppy ageKnown breed: typical missInside rangeMixed breed: typical missInside range
08–11 weeks17.8%78.6%21.0%80.5%
12–15 weeks14.8%79.1%16.6%80.9%
16–25 weeks11.6%79.2%12.4%80.3%
26–38 weeks9.0%79.9%9.2%80.4%
39–52 weeks6.9%79.4%7.0%79.8%

Held-out test, 120,000 weigh-ins. Full methods.

Puppy weight by breed

Breed pages give typical weight by age, from 2 to 12 months.

See all 335 breeds

More calculators

Common questions

How accurate is the puppy weight calculator?

We tested it on weigh-ins from dogs the method had never seen. The typical miss was about 11% of adult weight, and roughly 4 in 5 dogs finished inside the range shown. Accuracy improves with age: the typical miss is around 18% at 8 to 11 weeks and 7% after 9 months. The results table on the methods page has the full numbers.

How early can you predict a puppy's adult weight?

From 8 weeks, but treat anything before 12 weeks as a rough guide. Puppies grow in bursts, so a single early weigh-in can mislead. Weigh your puppy at the same time of day each week and run the calculator again at 4 to 5 months, when the range tightens a lot.

Does it work for mixed breeds?

Yes. Leave the breed blank and it works backwards from your puppy's age and weight alone, using the growth patterns of dogs of every size. The range is wider than for a known breed, because the calculator can't see how big the parents were.

Is the quick formula, weight divided by age in weeks times 52, good enough?

Not for puppies. It treats growth as a straight line, which it isn't. In our tests on 12 to 25 week puppies it was off by roughly 22% to 66% depending on adult size, against 11% to 13% for the curves used here.

What if my puppy is above or below the range for its breed?

That's common. Breed standards describe typical adults, and plenty of healthy dogs sit outside them. Body shape tells you more than the number: you should be able to feel the ribs under a thin layer of fat. If you're worried, ask your vet.

Growth curves: our analysis of Salt et al. (2017), PLOS ONE, CC BY 4.0. An estimate, not veterinary advice.