Estimate a popular human-year equivalent for a dog, cat, bird, hamster, or guinea pig.
| Human-year equivalent | – |
Use this calculator to convert a pet's calendar age into a widely used 'human years' equivalent. Select the species and enter the animal's age in years. Decimals are allowed (for example 2.5).
The calculation uses common rules of thumb, not a clinical ageing model. Charts from different sources disagree. Dog: 15 in year 1, plus 9 in year 2, then plus 5 per year. Cat: the same through year 2, then plus 4 per year. Bird: age × 9. Hamster: age × 25. Guinea pig: age × 8. Partial years are interpolated linearly within each interval.
This is a conversation number for comparing life stages. It is not a veterinary assessment of health or remaining lifespan. Breed, size, and health change how an individual ages.
Species: Which pet you are converting.
Age (years): The animal's age in calendar years.
Human-year equivalent: The estimated equivalent age in human years.
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