How we build our calculators
Every calculator uses published veterinary formulas and reference values, for example the resting energy formula used by vets for feeding, toxic dose levels from the Merck Veterinary Manual and life stage definitions from the AAHA and AAFP guidelines. Each page explains the math, shows a worked example and lists its sources, so you can check the numbers yourself.
All calculations run in your browser. There are no accounts, and the numbers you type are never sent to us.
Paws & Numbers gives general information, not veterinary advice. If you are worried about your pet's health, contact your veterinarian.