New Zealand pet calculators
Pets age much faster than people, and the idea of 'seven dog years to one human year' is only a rough guide. These calculators use newer research and veterinary guidelines to turn a pet's age into a human-equivalent age, and describe the life stage it is in, so you can plan checks and care.
Questions these calculators answer
How old is my dog in human years?
Use the formula 16 × ln(dog's age) + 31, from a 2020 DNA-methylation study of Labrador retrievers. A 7-year-old dog works out at about 62 in human years. A dog's first year is roughly 30 human years, the second adds about 10, and later years add fewer. Large breeds age faster, and small breeds a little slower.
How old is my cat in human years?
A cat is about 15 in human years at one, 24 at two, and gains four human years for every cat year after that. A 10-year-old cat is about 56 in human years. Cats of 10 are in the mature to senior range, so twice-yearly vet checks are sensible.
Why age matters for pets
A pet's life stage decides what it needs: vaccinations and desexing as a young animal, steady exercise and weight control as an adult, and more frequent vet checks as a senior. New Zealand dogs must be registered with the local council every year and most must be microchipped, while cats are not required to be, though microchipping is strongly recommended.
Human-equivalent age is an aid to thinking, not a medical measurement. Breed, size and health change how any individual animal ages, so use these tools as a conversation starter with your vet.
Other NZ sections
The health tools cover people; these cover your pets.