It is often said 1 human-year is equivalent to 7 dog-years. However, this simple conversion fails to recognize that dogs reach adulthood in their end year of life. As a result the American Kennel club suggests the following to calculate a dog's age in human-years.

15 human years are equivalent to the 1st year of a dog's life.

A dog's 2nd year is equivalent to 9 human years

After a dog's 2nd year each human year is approximately 5 dogs years

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