How does a dog’s age compare with a person’s? The answer is approximate, and the familiar seven-to-one rule is too simple. Breed, size and individual health affect how dogs develop and age.
Approximate age chart for a medium-sized dog
This table follows the American Veterinary Medical Association’s published comparison for dogs weighing 21–50 lb, approximately 9.5–23 kg. It replaces the older unsourced small/large-dog table on this page. It is not an exact conversion for every dog or a prediction of lifespan.
| Dog’s age (years) | Approximate human age (years) |
|---|---|
| 1 | 15 |
| 2 | 24 |
| 3 | 28 |
| 4 | 32 |
| 5 | 36 |
| 6 | 42 |
| 7 | 47 |
| 8 | 51 |
| 9 | 56 |
| 10 | 60 |
| 11 | 65 |
| 12 | 69 |
| 13 | 74 |
| 14 | 78 |
| 15 | 83 |
| 16 | 87 |
Source: AVMA: Pets age faster than people (PDF).
Use the estimate in context
A human-age comparison cannot assess pain, fitness or health. Ask your vet about the care suited to your dog’s life stage. For more detail, the working calculator and our factsheet, see Understanding Your Dog’s Age in Human Years.
Table reviewed October 2026. Originally published 23 February 2014 by Justin Jordan.
