TL;DR
There is no single "dog years" number, and the old rule of multiplying by 7 is wrong: dogs age very fast in their first two years and more slowly after that, and small breeds age more slowly than giant ones. Our calculator below gives three answers side by side, each from published research: a human age from DNA changes (a 2020 study of Labradors), the same point in a human life based on your breed's typical lifespan (a 2024 study of 584,734 dogs across 155 breeds), and your dog's life stage using the American Animal Hospital Association (AAHA) definitions, including the age your breed counts as senior.
Dog age calculator
Enter your dog's age and breed. Choose "Mixed breed" if you are not sure.
Human age (DNA method)
64
From age-related DNA changes in Labradors compared with people (Wang 2020). Least reliable for puppies under a few months.
Same point in a human life
53
Your dog has lived about 67% of the typical 12.0-year lifespan for this group. The same share of a 79.0-year US life expectancy is age 53.
Life stage
Mature adult
AAHA: from maturity until the last 25% of expected lifespan, about 9.0 years for this group.
Mixed breed (crossbreed): median lifespan 12.0 years (95% CI 12.0 to 12.1), senior from about 9.0 years.
Lifespans: UK study of 584,734 dogs (McMillan 2024). Life stages: AAHA. Every dog ages differently; health, weight and lifestyle all matter.
How the calculator works
1. Human age from DNA changes
As animals age, chemical tags on their DNA (methylation) change in a predictable way. A 2020 study in Cell Systems compared these changes in 104 Labrador Retrievers with those in people and produced the formula:
human age = 16 × ln(dog age) + 31
where ln is the natural logarithm. It explains why a 1-year-old dog is already like a 31-year-old person, while the years after that add much less. The limitation: it was built on one breed, Labradors, so it does not account for size.
2. The same point in a human life
This method uses your dog's breed. We divide your dog's age by the median lifespan for its breed, the age by which half of dogs of that breed have died, from a 2024 study of 584,734 dogs in the UK. Then we apply that share to US life expectancy, which was 79.0 years in 2024 according to the CDC.
For example, a 10-year-old Pug has lived about 86% of the Pug median of 11.6 years. The same share of 79 years is about 68. A 10-year-old Labrador (median 13.1 years) has lived about 76% of its typical lifespan, the same point as a 60-year-old person.
This is a comparison of life stages, not a medical age, and the calculator shows it from 1 year of age: puppies develop far faster than their share of lifespan suggests. It does capture what the DNA formula misses: a 10-year-old French Bulldog and a 10-year-old Poodle are at very different points in their lives.
3. Life stage
The 2019 AAHA Canine Life Stage Guidelines define five stages:
- Puppy: birth until rapid growth ends, about 6 to 9 months
- Young adult: until physical and social maturity, usually by 3 to 4 years
- Mature adult: until the last 25% of estimated lifespan
- Senior: the last 25% of estimated lifespan
- End of life: a terminal stage that depends on illness, not age
Because AAHA defines senior by estimated lifespan, not a fixed age, the calculator works out the senior age for your breed: 75% of the breed's median lifespan. A crossbreed with a median of 12.0 years becomes senior at about 9; a Cane Corso (median 8.1) at about 6.
Dog years to human years chart (DNA method)
| Dog age | Human age (DNA method) |
|---|---|
| 3 months | 9 |
| 6 months | 20 |
| 1 year | 31 |
| 2 years | 42 |
| 3 years | 49 |
| 4 years | 53 |
| 5 years | 57 |
| 6 years | 60 |
| 7 years | 62 |
| 8 years | 64 |
| 9 years | 66 |
| 10 years | 68 |
| 11 years | 69 |
| 12 years | 71 |
| 13 years | 72 |
| 14 years | 73 |
| 15 years | 74 |
| 16 years | 75 |
Values from the Wang 2020 formula, rounded. Remember it is based on Labradors: for small, long-lived breeds the real figures are probably lower in later life, and for giant breeds higher. Use the breed table below for that.
Lifespan and senior age by breed
Median lifespans from the 2024 UK study of 584,734 dogs. "Senior from" is 75% of the median, following AAHA. The last column uses method 2 above.
| Breed | Median lifespan (years) | Senior from about | At age 10, same point in a human life |
|---|---|---|---|
| Mixed breed (crossbreed) | 12.0 | 9.0 | 66 |
| Labrador Retriever | 13.1 | 9.8 | 60 |
| Golden Retriever | 13.2 | 9.9 | 60 |
| German Shepherd Dog | 11.3 | 8.5 | 70 |
| French Bulldog | 9.8 | 7.4 | 81 |
| Bulldog | 9.8 | 7.4 | 81 |
| Poodle | 14.0 | 10.5 | 56 |
| Beagle | 12.5 | 9.4 | 63 |
| Rottweiler | 10.6 | 7.9 | 75 |
| Dachshund | 13.2 | 9.9 | 60 |
| Miniature Dachshund | 14.0 | 10.5 | 56 |
| Yorkshire Terrier | 13.3 | 10.0 | 59 |
| Boxer | 11.3 | 8.5 | 70 |
| Pembroke Welsh Corgi | 13.2 | 9.9 | 60 |
| Siberian Husky | 11.9 | 8.9 | 66 |
| Shih Tzu | 12.8 | 9.6 | 62 |
| Great Dane | 10.6 | 7.9 | 75 |
| Cavalier King Charles Spaniel | 11.8 | 8.9 | 67 |
| Miniature Schnauzer | 13.3 | 10.0 | 59 |
| Pug | 11.6 | 8.7 | 68 |
| Chihuahua | 11.8 | 8.9 | 67 |
| Border Collie | 13.1 | 9.8 | 60 |
| Jack Russell Terrier | 13.3 | 10.0 | 59 |
| Bernese Mountain Dog | 10.1 | 7.6 | 78 |
| Staffordshire Bull Terrier | 12.0 | 9.0 | 66 |
| Cane Corso | 8.1 | 6.1 | 98 |
| Australian Shepherd | 13.7 | 10.3 | 58 |
| Maltese | 13.1 | 9.8 | 60 |
| Pomeranian | 12.2 | 9.1 | 65 |
| Shiba Inu | 14.6 | 10.9 | 54 |
| Doberman Pinscher | 11.2 | 8.4 | 71 |
| Whippet | 13.4 | 10.1 | 59 |
| English Cocker Spaniel | 13.3 | 10.0 | 59 |
| Boston Terrier | 11.8 | 8.9 | 67 |
| Havanese | 14.5 | 10.9 | 54 |
The calculator above includes all 155 breeds in the study. Some breeds had few recorded deaths, so their figures are less precise; the calculator flags these.
Why the "multiply by 7" rule is wrong
- Dogs grow up fast. The DNA study puts a 1-year-old dog at about 31 in human terms, not 7.
- Ageing slows after that. In the DNA formula, from about age 6 onward each extra year adds only one or two human years.
- Breed and size matter. In the 2024 study, small purebreds lived longest (median 12.7 years for males, 12.8 for females), then medium (12.3 and 12.7), then large (11.8 and 12.0). Breeds ranged from a median of 5.4 years (Caucasian Shepherd Dog) to 15.4 (Lancashire Heeler).
- Face shape matters. Flat-faced (brachycephalic) breeds were among those most at risk of dying young. French Bulldogs had a median of 9.8 years, and medium-sized flat-faced purebreds as a group 9.4 years.
What your dog's age means for care
- Senior from the age in the table: AAHA's 2023 senior care guidelines recommend more frequent check-ups for seniors, and VCA Animal Hospitals suggests about every six months. See when is a dog considered senior?
- Watch for changes that owners often put down to "just age": stiffness, weight or muscle loss, changes in appetite or thirst, night-time restlessness. See senior dog care guide.
- Keep your dog lean. In a lifelong study of 48 Labradors, dogs fed 25% less than their littermates lived a median of 13.0 years against 11.2.
- Support joints, brain and teeth as your dog moves into its senior years. See senior dog supplements ranked by evidence.
FAQ
How old is my dog in human years?
It depends on the method and the breed. By the DNA formula, a 1-year-old dog is about 31, a 5-year-old about 57 and a 10-year-old about 68. By breed lifespan, a 10-year-old Labrador is at the same point as a 60-year-old person, a 10-year-old French Bulldog at 81. Use the calculator for your dog.
Is one dog year really seven human years?
No. Dogs age much faster than that in the first year or two, and more slowly afterwards, and the pace depends on breed and size.
How do you calculate a dog's age in human years?
The DNA method uses human age = 16 × ln(dog age) + 31. The breed method divides your dog's age by its breed's median lifespan and applies that share to a human life expectancy of 79 years.
At what age is a dog considered a senior?
In the last 25% of its expected lifespan, according to AAHA. For a crossbreed that is about 9 years; for a Labrador about 9.8; for a French Bulldog about 7.4; for a Shiba Inu about 10.9.
Which dog breeds live the longest?
In the 2024 UK study, the longest median lifespans were the Lancashire Heeler (15.4 years), Tibetan Spaniel (15.2), Bolognese (14.9), Shiba Inu (14.6), and Havanese and Papillon (14.5 each). Several of these rest on fewer than 100 recorded deaths. Among breeds with large samples, the Border Terrier (14.2 years, from 2,427 deaths) and the Miniature Dachshund and Poodle (14.0 each) stand out.
How long do pugs live?
The median lifespan for Pugs in the 2024 UK study was 11.6 years, below the 12.0 years for crossbreeds. A Pug is senior from about 8.7 years.
References
- McMillan KM, et al. Longevity of companion dog breeds: those at risk from early death. Scientific Reports. 2024. PMID: 38302530. Breed medians from Supplementary Table 3.
- Wang T, et al. Quantitative translation of dog-to-human aging by conserved remodeling of the DNA methylome. Cell Systems. 2020. PMID: 32619550
- Creevy KE, et al. 2019 AAHA Canine Life Stage Guidelines. Journal of the American Animal Hospital Association. 2019. PMID: 31622127
- American Animal Hospital Association. 2023 AAHA Senior Care Guidelines: defining the senior patient.
- Xu J, et al. Mortality in the United States, 2024. NCHS Data Brief No. 548. Centers for Disease Control and Prevention. 2026.
- Kealy RD, et al. Effects of diet restriction on life span and age-related changes in dogs. Journal of the American Veterinary Medical Association. 2002. PMID: 11991408
- VCA Animal Hospitals. Senior Dog Care.
For individual health questions, your veterinarian remains the best partner.
