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Dog Age Calculator

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📊 Data: ASPCA, AVMA, PetMD
📅 Updated Mar 2026

📅 Dog Age Calculator

Enter your dog’s age and size to get their real human equivalent

years old

Why the “7 Dog Years = 1 Human Year” Rule Is Wrong

The popular idea that one dog year equals seven human years is a myth. A 2019 study in Cell Systems used DNA methylation to develop a more accurate formula — a 1-year-old dog is already equivalent to a 31-year-old human.

How Dog Age Varies by Size

Large breeds age faster than small breeds. A 10-year-old Great Dane is elderly while a 10-year-old Chihuahua is still in middle age.

  • Small breeds (under 20 lbs) — Live 14–16 years on average
  • Medium breeds (20–50 lbs) — Live 12–14 years
  • Large breeds (50–90 lbs) — Live 10–12 years
  • Giant breeds (over 90 lbs) — Live 8–10 years