How to use the puppy weight calculator
- Weigh your puppy. For a small puppy, a kitchen or baby scale is most precise. For a bigger one, weigh yourself holding the puppy and subtract your own weight.
- Enter the weight and the age in weeks or months. The estimate works from 8 weeks to 2 years (24 months).
- Pick the breed from the list of 282 AKC breeds, which sets the size and shows the breed's standard, or pick the size yourself by the typical adult weight of the breed, or of the parents for a mixed breed: toy (under 12 lb), small (12 to 24 lb), medium (25 to 50 lb), large (51 to 100 lb) or giant (over 100 lb).
The result is the most likely adult weight and a likely range. The growth curve and the table show the path ahead from today's weigh-in to the adult weight, with the range opening out from today's weight. Share result makes a link with the weigh-in, the age, the size and the breed.
Tracking several weigh-ins
Choose Track several, enter your puppy's date of birth and add a weigh-in whenever you weigh it: the date and the weight. They are saved in this browser, on this device only, and plotted on the growth curve.
Each weigh-in makes its own estimate of the adult weight, and the tracker averages them. Later weigh-ins get more say, because puppies of the same age are more alike the older they are; the list shows each weigh-in's estimate and its share of the say. The likely range is the one from your latest weigh-in alone. Weigh-ins of one puppy aren't independent measurements, so adding more doesn't make the range narrower than the latest one allows. What they do is keep an odd early reading, such as a weigh-in after a big meal, from pulling the estimate far off. The latest reading has the most say and sets the range, so if it looks odd, weigh again. When a weigh-in is lower than the one before it, the tracker says so: a small dip can come from a different scale or the time of day, but if your puppy is losing weight, ask your vet.
Near 2 years old the range's low end would fall below today's weight, because some dogs in the data were a little heavier at 2 than later. The calculator raises it to today's weight and says so under the result.
Where the numbers come from
In 2017, researchers from the WALTHAM Centre for Pet Nutrition and the University of Liverpool (Salt and colleagues, in PLOS ONE) published growth standards for dogs from the records of Banfield Pet Hospitals, a network of US vet clinics, and made the underlying data openly available. We used that data directly: purebred dogs never recorded as thin or overweight, weighed both as puppies and again at 2 to 3 years old. That is about 390,000 dogs of 31 breeds (the data hides breed names).
For each dog we worked out what share of its own adult weight it had reached at each visit, and grouped the dogs by the typical adult weight of their breed. The calculator divides your puppy's weight by the share a typical puppy of its size had reached at the same age. For the range, it does the same with the spread between puppies: at each age, 8 in 10 had reached between a lower and a higher share (the hero line shows both), and your puppy's weight divided by those gives the likely span.
What "adult weight" means here, and when puppies stop growing
The calculator's adult weight is a dog's weight at 2 to 3 years old. Salt and colleagues describe very small breeds reaching maturity at 8 to 12 months and larger breeds needing up to 24 months to reach adult body weight. Their data also shows something those milestones hide: dogs of every size kept gaining slowly after their first birthday, toy breeds included. At one year a toy dog weighed about 88% of its 2-to-3-year weight, a large dog about 91%. Some of that later gain is probably filling out rather than growing, and the data can't tell the two apart.
So read the At 1 year figure as where a typical puppy of that size is at its first birthday, not as the moment growth stops, and the adult weight as a little above the weight at which a small dog is usually called fully grown.
The giant curve rests on only 2 breeds and about 5,000 dogs, far fewer than the others, so treat giant estimates with extra care. The published charts themselves only cover breeds up to 40 kg.
Quick multipliers
The same curves as simple rules of thumb: multiply the weight at each age by the number for your puppy's size to get the most likely adult weight.
| Age | Toyunder 12 lb | Small12–24 lb | Medium25–50 lb | Large51–100 lb | Giantover 100 lb |
|---|---|---|---|---|---|
| 8 weeks | × 3.8 | × 4.4 | × 5.4 | × 6.6 | × 8.2 |
| 12 weeks | × 2.7 | × 2.9 | × 3.3 | × 3.8 | × 4.4 |
| 16 weeks | × 2.0 | × 2.1 | × 2.3 | × 2.5 | × 2.9 |
| 6 months | × 1.4 | × 1.4 | × 1.5 | × 1.5 | × 1.6 |
| 9 months | × 1.2 | × 1.2 | × 1.2 | × 1.2 | × 1.2 |
| 1 year | × 1.1 | × 1.1 | × 1.1 | × 1.1 | × 1.1 |
The popular "double the weight at 16 weeks" rule works for toy and small breeds, but a large-breed puppy at 16 weeks is only about 40% of the way there.
Reading the result
- The range is wide for young puppies and narrows as they grow: at 12 weeks it spans roughly 25% below to 40% above the middle value. Weigh every two to four weeks, on the same scale, and the estimates will settle.
- Grown so far is the share of adult weight a typical puppy of that size has reached at this age.
Growth is not a race. A puppy that tracks above or below the curve can be perfectly healthy; what matters is body condition, which your vet checks by look and feel. If your puppy stops gaining, loses weight or seems too thin or heavy, ask your vet.
Once your dog is grown, the dog age calculator converts its age to human years by size. Planning feeding times or walks? The timer works on any phone.
Sources, checked September 2026: Salt C, Morris PJ, German AJ, Wilson D, Lund EM, Cole TJ, Butterwick RF, Growth standard charts for monitoring bodyweight in dogs of different sizes, PLOS ONE 12(9): e0182064 (2017); the supporting data, University of Liverpool DataCat (CC BY 4.0). The curves are our own analysis of that data, not the published charts. Breed standards: each breed's page on akc.org (linked when you pick it), read September 2026. Not veterinary advice.