Full report JSON
How it works
Pet years describe developmental stages rather than a fixed multiple of human years. Young animals mature quickly, while later estimates depend on species, size and individual health.
What you can do
Choose cat or a dog size model and convert in either direction. At pet age1 this model gives15 human years, at2 it gives24. Later each pet year adds4 for cats/small dogs,5 for medium,6 for large or7 for giant dogs.
How to use it
- Choose species, size and direction. Enter decimal years, one age per line; 1.5 means one year and six months.
- Calculate, review the approximate years and formula report, then copy or download. Changes clear old results; undo restores previous input.
Errors and limits
This educational model interpolates linearly between0,1 and2 pet years. It is not a breed-specific veterinary table or lifespan prediction. Up to100 ages; pet0–30 or human0–150, at most4 decimals. Inverse results above30 pet years are rejected. Output rounds to4 decimals.
Frequently asked questions
Why do other calculators show different ages?
There is no universal exact conversion. Different charts use different early-life anchors and later rates. Compare the published formula, not just the result; ask a veterinarian about health or care.
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