About puppyweightcalculator.co
puppyweightcalculator.co is a free, independent set of tools that help dog owners answer a simple question: how big will my puppy get? Everything is free to use, with no sign-up, no login and no limits.
Our tools
Everything here is free, runs in your browser, and needs no account.
- Puppy weight calculator: estimate a puppy's adult weight from its breed, age and current weight, with a range rather than a single number, and the parents' weights if you know them.
- Puppy growth chart: expected weight by age for all five size classes, in pounds and kilograms, with the percentage of adult weight reached at each age. Breed-specific charts for the German Shepherd and the Labrador Retriever split the figures by sex.
- Dog litter size calculator: estimate how many puppies to expect in a litter from the dam's breed size and age.
Our methodology
Our puppy weight calculator uses the percentage-of-adult-weight method: it estimates adult weight by dividing your puppy's current weight by the fraction of adult weight a dog of that size class has typically reached at its current age. The growth curves are modelled on published canine growth research and standard breed size classes, and every tool shows its own "Sources & methodology" section.
The full model is published on the methodology page: the complete growth curve as downloadable open data, the sources it was calibrated against, worked examples of every calculation, and an explicit account of what has not yet been validated.
Sources we rely on
- Salt C, et al. (2017). "Growth standard charts for monitoring bodyweight in dogs of different sizes." PLOS ONE 12(9): e0182064.
- WALTHAM Petcare Science Institute: puppy growth charts and size-class references.
- Breed size standards from recognised kennel clubs, including the American Kennel Club (AKC).
- WSAVA Global Nutrition Committee: body condition score guidelines.
Our commitment
- Free and open: no account, no paywall.
- Private: the calculators run in your browser; we don't store your puppy's details.
- Honest: every result is clearly labelled an estimate with a stated margin, and is not a substitute for veterinary advice.
Editorial standards
Our content is grounded in the cited, published research above rather than opinion. We are adding a named, credentialed veterinary reviewer to further strengthen our editorial process; until then, our methodology and sources are published transparently on every tool so you can check the basis of each estimate yourself.
Contact
Feedback or corrections are welcome at hello@puppyweightcalculator.co.