Dog Age Calculator

The AVMA's rule gives the first year 15 human years and the second year adds 9 more (24 total by age 2) for every size. After that, each additional dog year adds human-years at a size-dependent rate — small breeds age more slowly (about 4 human years per dog year), while giant breeds age faster (about 8), because larger dogs have shorter average lifespans.

A 2020 study (Wang et al.) found that DNA methylation patterns in Labrador Retrievers follow a logarithmic curve: human age ≈ 16 × ln(dog age) + 31. It ages young dogs faster than the AVMA rule but was derived from one breed, so it may be less accurate for very small or very large breeds.

Large and giant breeds tend to age faster and have a higher incidence of certain age-related diseases at younger ages, likely linked to faster early-life growth rates — this is a well-documented pattern across dog breeds, the opposite of the general trend seen across different animal species.

Puppy (0-6 months), Adolescent (6 months-2 years), Adult, Mature Adult, Senior, and Geriatric — the ages marking Senior and Geriatric stages shift earlier for larger breeds, reflecting their shorter average lifespans.