Cat Age Calculator
A cat age calculator estimates human years by counting the first cat year as about 15 human years, the second as 9 more, and later years as about 4.
How Old Is My Dog or Cat in Human Years?
Use the calculator below to estimate your pet's age in human years. Dogs are estimated by age and size, while cats use a first-year, second-year, and adult-year formula.
- Dog sizes: small, medium, large, and giant.
- Cat estimate: first year 15, second year 9, then about 4 human years per cat year.
- Use the result as a guide, not a veterinary diagnosis.
Human years
years
A 4-year-old small dog is a settled adult.
Dog estimate: first year 15, second year 9, then small +4, medium +5, large +6, giant +7 each year.
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Senior Dog Age Chart
A senior dog age chart helps owners understand when small, medium, large, and giant dogs may enter older life stages.
Dog Age Calculator by Size
A dog age calculator is more useful when it accounts for size, because small dogs, large dogs, and giant dogs age differently after maturity.
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Dog Guides Dog age calculators, dog years explainers, breed size guides, and life-stage articles. Cat Guides Cat age calculators, cat years explainers, and kitten-to-senior life-stage articles. Senior Care Older dog and cat articles covering senior age, food, comfort, and care questions. Food & Safety Dog food by age, safe human foods, toxic-food warnings, and feeding topics.
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