Animal years compared: age in human years
| Animal | 1 year | 2 years | 3 years | 5 years | 10 years | 15 years |
|---|---|---|---|---|---|---|
| Dog (medium) | 15 | 24 | 28 | 36 | 60 | 83 |
| Cat | 15 | 24 | 28 | 36 | 56 | 76 |
| Rabbit | 8 | 16 | 24 | 40 | 80 | — |
| Guinea pig | 13.3 | 26.7 | 40 | 66.7 | — | — |
| Hamster | 32 | 64 | 96 | — | — | — |
| Horse | 2.9 | 5.7 | 8.6 | 14.3 | 28.6 | 42.9 |
How to use the Animal Age Calculator
- 1 Choose the animal.
- 2 Enter its age in years and months (for dogs, also pick the size).
- 3 Read the age in human years and the matching life stage.
Why “times seven” is wrong
The old rule that one animal year equals seven human years is a myth – and it was never meant for every animal. Most pets grow up very quickly: a one-year-old dog or cat is already comparable to a teenager, while ageing slows down later in life. How fast an animal ages also depends on its species and, for dogs, on its size.
How this calculator works
- Dogs use the widely published veterinary age chart: the first year counts as about 15 human years, the second as about 9 more, and every year after that as 4 to 7 years depending on size – large breeds age faster. You can also switch to the epigenetic formula from a 2019 DNA study.
- Cats use the chart recommended by feline welfare organisations: 15 human years after the first year, 24 after the second and 4 more for every year after that.
- Rabbits, guinea pigs, hamsters and horses have no generally accepted chart, so the calculator compares the animal’s age with a typical lifespan for its species and scales it to a human lifespan of 80 years.
Fractional ages are interpolated, so a dog of 6 years and 6 months sits halfway between the 6- and 7-year values.
Life stages
Next to the number you see a life stage – from youngster to senior. Knowing that your pet is entering its senior years is a good moment to talk to your vet about check-ups, diet and exercise.
A rough guide, not a diagnosis
Breed, genetics, diet, exercise and medical care all influence how an individual animal ages. Use the result as a fun and useful indication, not as veterinary advice.
Frequently asked questions
Is one dog year really seven human years?
No. Dogs mature much faster in their first two years and then age more slowly, and big dogs age faster than small dogs. The chart used here reflects that.
Which animal ages the fastest?
Of the animals in this calculator, hamsters: with a typical lifespan of 2–3 years, one hamster year corresponds to roughly 30 human years.
How accurate are these results?
They are estimates. Dog and cat values follow commonly used veterinary charts; for the other animals the result is based on typical lifespans.
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