Dog Age Calculator

No. Dogs mature quickly, so the first year alone is worth about 15 human years and the second adds roughly 9 more. A flat factor of 7 understates a young puppy and overstates a senior dog, which is why neither method here uses it.

A 2019 study compared DNA methylation in dogs and humans and derived human age equals 16 times the natural log of the dog's age, plus 31. This tool uses it as the default and it is defined for any age greater than zero.

It counts the first year as about 15 human years, the second as about 9 more so age 2 is near 24, then adds a fixed amount for each later year based on breed size. That per-year amount is 4 for small, 5 for medium, 6 for large, and 8 for giant dogs.

The size menu appears only when Traditional is selected because that is the method that varies the later years by size. The epigenetic formula was fit across breeds and does not take a size input, so its result is the same regardless of breed.

Small breeds tend to live longer and age more slowly after they mature, while giant breeds reach old age sooner. The traditional method reflects that by adding as little as 4 or as many as 8 human years per dog year once a dog is past age two.

Yes. Enter a decimal such as 0.5. Under the traditional method a half-year dog reads as about 7.5 human years, while the epigenetic formula also accepts any age above zero.

They model aging differently. The epigenetic curve rises fast then flattens, so it can read higher for middle-aged dogs, while the size-based method climbs at a steady per-year rate. Both are estimates, so expect a gap rather than a single true answer.

Yes. The conversion runs entirely in your browser and nothing is uploaded, so the age you enter and the result stay on your device.

No. These formulas estimate a typical age and cannot judge your individual dog. A veterinarian can assess health, breed, and life stage far more accurately, so treat the number as a fun, rough guide.