Dog Age Calculator
Find out how old your dog is in human years, adjusted for size, and see its life stage.
- By size
- AVMA chart
- Epigenetic formula
- Life stage
Dog age in human years
Fill in the boxes. The answer appears as you type.
How do you convert dog years to human years?
The old “multiply by seven” rule is a myth. Dogs mature very quickly: a one-year-old dog is roughly like a 15-year-old human, and two years equals about 24. After that, ageing depends on size, because large and giant breeds age faster than small dogs. This calculator uses the size-based chart published by the American Veterinary Medical Association and also shows the epigenetic clock formula from a 2020 study of Labrador retrievers: human age = 16 × ln(dog age) + 31.
How to use Dog Age Calculator
- Enter your dog’s age in years (decimals like 2.5 are fine).
- Choose its adult size.
- Read the age in human years and its life stage.
- Compare with the epigenetic formula and the old × 7 rule.
Dog age chart (human years)
- 1 year ≈ 15 · 2 years ≈ 24 for every size.
- 5 years: ≈ 36 (small, medium and large), 45 (giant).
- 10 years: ≈ 56 (small), 60 (medium), 66 (large), 79 (giant).
- Dogs are usually considered seniors at 7 (large) to 10 (small) years.
Why use this dog age calculator
- Answers as you typeNo Calculate button. Change any number and every result updates instantly.
- Clear, sourced rules of thumbEach formula is named and explained, so you know where the number comes from and its limits.
- Size mattersSmall, medium, large and giant breeds age at different rates; the old × 7 rule ignores this.
- PrivateYour numbers are calculated on your device and never sent anywhere.
Common uses
- Curiosity. How old is my dog really?
- Senior care. Know when your dog becomes a senior.
- Adoption. Understand a rescue dog’s stage of life.
- Kids and education. Explain ageing in dogs.
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Example: a 7-year-old Labrador
Large breed, 7 years → about 50 human years (mature adult). The epigenetic formula gives 16 × ln(7) + 31 ≈ 62.
What to expect from the result
Breed, genetics and health affect ageing; the result is an approximation for fun and general guidance, not a veterinary assessment.
Dog Age Calculator questions
How many human years is one dog year?
The first dog year equals about 15 human years and the second about 9. After that it is about 4–7 human years per dog year, depending on size.
Is the “dog years × 7” rule true?
No. It underestimates young dogs and does not account for size; large breeds age faster than small ones.
How old is a 10-year-old dog in human years?
About 56 for small dogs, 60 for medium, 66 for large and 79 for giant breeds.
What is the epigenetic dog age formula?
Human age = 16 × ln(dog age) + 31, from a 2020 study that compared DNA methylation in Labradors and people.
When is a dog a senior?
Generally at around 7 years for large and giant breeds and 10 years for small breeds.