Dog Age Calculator

Enter your dog's age in dog years and the calculator applies the epigenetic-clock formula from Wang et al. (Cell Systems, 2019, UC San Diego): human_age = 16 × ln(dog_age) + 31, where ln is the natural logarithm. It then shows the human-age equivalent and a life stage — puppy, young adult, mature adult, senior or geriatric. Results are approximate and vary by breed.

No. The multiply-by-7 rule treats dog aging as linear, but dogs mature very quickly in their first year and then age more slowly. Under the epigenetic formula a 1-year-old dog is closer to a 30-year-old human than to a 7-year-old, and a 13-year-old dog is closer to 73 in human-age terms than to 91.

The formula uses an average curve, so the number on screen is the same for every breed — but size meaningfully changes life expectancy. Small breeds under 20 lb typically live 14-16 years and are senior by 9-10, while giant breeds over 90 lb typically live 7-10 years and are senior by 5-6. Treat the result as a starting point and ask your veterinarian for breed-specific senior-care timing.

About 68 human years under the epigenetic formula (16 × ln(10) + 31), compared with 70 under the old 7× rule. Either way a 10-year-old dog is in the senior stage — a large-breed dog at that age is firmly senior and benefits from twice-yearly exams plus annual bloodwork.

It is based on measured DNA-methylation changes rather than a folk rule, so it tracks real biological aging far better than multiplying by 7. It is still an approximation: it is most reliable for dogs over 1 year old, puppies under 12 months grow quickly and unevenly, and it does not adjust for breed or size. Use it to understand your dog's life stage, not as a substitute for a veterinary exam.