Frequently Asked Questions

We use species-specific formulas based on average lifespans from veterinary literature and scientific research. For dogs, we use a logarithmic formula based on epigenetic aging research published in Cell Systems. For cats, we follow AAHA/AAFP Feline Life Stage Guidelines. For other species, we use proportional lifespan mapping — taking the average captive lifespan and mapping it to a human lifespan of 80 years, with a curve applied to reflect rapid early growth.

They are estimates based on average species lifespans — not a precise biological measurement. Individual animals vary enormously based on genetics, diet, environment, and veterinary care. A well-cared-for ball python may live years longer than the average. Think of our conversions as a meaningful frame of reference, not a scientific certainty.

The "multiply by 7" rule for dogs was always an oversimplification — and for any other animal, it's completely meaningless. A 1-year-old dog is sexually mature and nearly full-grown, which is much closer to a 15–30 year old human than a 7-year-old. Animals age at non-linear rates, especially in their early years. We use formulas that actually reflect this.

For pet animals — snakes, lizards, hamsters, rabbits — we use captive lifespans, since most people asking this question own a pet. For wild animals — elephants, dolphins, sharks — we use wild lifespans, since these animals are rarely kept in captivity. We note which we're using on each calculator page.

No. All calculations happen entirely in your browser using JavaScript. Your pet's age, species, and any other inputs never leave your device and are never transmitted to our servers. See our Privacy Policy for full details.

PawClocks does not set first-party cookies. Google Analytics (which we use for anonymous traffic data) may set analytics cookies. You can disable these in your browser settings without affecting the calculators.

Research published in Science in 2016 estimated that Greenland sharks can live at least 272 years, with one specimen estimated to be up to 512 years old. They grow only about 1 cm per year. A Greenland shark alive today may have been born before the United States existed.

Hamsters live only 2–3 years on average. Mapped to a human lifespan of 80 years, even a 1-year-old hamster is equivalent to roughly a 30–40 year old human. Small animals with short lifespans age extraordinarily fast relative to humans — their hearts beat 300–500 times per minute, and their metabolism runs at a pace we can barely comprehend.

Technically yes — Turritopsis dohrnii, the so-called immortal jellyfish, can revert to its juvenile polyp stage after reaching sexual maturity, essentially cycling through its life stages indefinitely. This makes calculating a "human age equivalent" rather philosophically challenging, which we acknowledge on its calculator page.

Absolutely. We're always expanding. Use our Contact page and select "Suggest a new animal calculator." The more specific the better — tell us the species, why you're curious, and whether it's a pet you own or a wild animal you're fascinated by.

Please use our Contact page and select "Report an error." Include the calculator name, what looks wrong, and if possible a source that shows the correct information. We investigate every report and fix confirmed errors promptly.

We source lifespan data primarily from the IUCN Red List, the American Veterinary Medical Association, the Association of Zoos and Aquariums, and peer-reviewed scientific literature. Each calculator page links to its specific sources.