Simple calculators for dog and cat owners
Age in human years, daily food, puppy size and more. Every formula is shown on the page and every source is named, so you can see where the numbers come from.
Most used
All calculators
Age
Feeding
Growth and health
How we get the numbers
Published formulas
Feeding amounts start from the standard veterinary formula for resting energy, 70 times body weight in kilograms to the power 0.75, multiplied by a life stage factor. Age charts follow the veterinary guidelines for cats and dogs, and the 2020 dog aging research formula.
Measured data
Puppy size and weight charts use growth curves fitted to real puppies weighed over time in a published study. Pregnancy dates use the gestation ranges reported in veterinary reproduction sources.
Shown in the open
Each page explains its formula, lists its sources and gives the date it was last reviewed. Where a number is a rule of thumb or comes from a small study, the page says so.
Why you can trust the numbers
- Nothing is hidden. You can follow every result from your input to the formula on the page.
- We do not recommend products inside the calculators. Results never depend on a brand.
- The limits are stated. These are estimates for general information, and the pages tell you when to ask your vet.
- Your data stays with you. Every calculator runs in your browser, and nothing you type is sent to us.
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