Free pet calculator
Dog Age Calculator
Your dog's age in human years — size-adjusted, not the old ×7 myth.
Showing an example
Not veterinary advice. This is a general age-equivalence estimate for informational purposes only — it does not replace professional judgment. If you're concerned, contact a veterinarian. This is a general age-equivalence estimate based on population-level aging curves, not a clinical or biological measurement of your dog's health or aging — individual dogs vary by breed, genetics, and health history.
Sources & how this is calculated
The old "1 dog year = 7 human years" rule has no veterinary basis — dogs mature far faster than humans in their first two years, and how fast they age afterward depends heavily on size. The base of the curve used here is the American Veterinary Medical Association guidance published by the American Kennel Club : a dog’s first year equals about 15 human years, the second year adds about nine more (24 in total), and every year after that adds roughly five. That last step depends on size, and the size-specific version used here comes from PetMD’s dog-age guide, written by Jennifer Coates, DVM , which gives four human years per year for small dogs, four to five for medium, five to six for large, and seven to eight for giant. This calculator takes one value from each of those bands — 4, 5, 6 and 7 — so the result is a single number rather than a spread.
The weight bands themselves are this tool’s own — veterinary sources do not agree on one set — so here they are in full: under 20 lb is small, 20 lb up to 50 lb is medium, 50 lb up to 90 lb is large, and 90 lb and over is giant. A dog sitting exactly on 20, 50 or 90 lb falls in the larger band. The AKC’s own printed chart draws its lines at 20 / 50 / 100 lb instead, so a 95 lb dog is “giant” here and “large” there.
This is a population-level estimate, not a measurement of your individual dog's biological age — breed, genetics, and health history all affect real aging rate. For a genuine assessment of your dog's health or life stage, talk to your veterinarian.