What 3 years means for a medium dog
This page covers medium dogs, meaning 21–50 lb (10–23 kg), such as a Beagle or Cocker Spaniel. At 3 years, they are in the adult stage (2–6 years). Settled, fit, and at their peak. Regular exercise and yearly vet checks keep them there.
A medium dog is usually considered a senior from about 7. A 3-year-old medium dog comes out at about 28 in human years, up from about 24 at 2 years.
Care notes for the adult stage
- Book a yearly check-up with boosters and a dental check.
- Keep their weight in check, since extra weight strains joints.
- Give regular exercise suited to their breed and size.
3 years and beyond, month by month
Dogs don't age in whole-year jumps. Here is how the human equivalent grows for a medium dog after 3 years.
| Medium dog's age | Human years |
|---|
| 3 years | 28 |
| 3 years 1 month | 28 |
| 3 years 2 months | 29 |
| 3 years 3 months | 29 |
| 3 years 4 months | 30 |
| 3 years 5 months | 30 |
| 3 years 6 months | 31 |
| 3 years 7 months | 31 |
| 3 years 8 months | 31 |
| 3 years 9 months | 32 |
| 3 years 10 months | 32 |
| 3 years 11 months | 33 |
3-year-old dogs by size
Bigger dogs age faster after the first two years, so the same calendar age means a different human age.
| At 3 years | Weight | Human years | Life stage |
|---|
| Small | Up to 20 lb (9 kg) | 28 | Adult |
| Medium | 21–50 lb (10–23 kg) | 28 | Adult |
| Large | 51–90 lb (23–41 kg) | 30 | Adult |
| Giant | Over 90 lb (41 kg) | 32 | Adult |
A 3-year-old cat comes out at 28.
Common questions
Is a 3-year-old medium dog old?
No. A medium dog this age is an adult, and a medium dog is usually considered a senior from about 7.
How many human years does one more dog year add?
For a medium dog at this age, about 4.
Does breed change the conversion?
Size is the biggest factor the chart accounts for. Breed, health, and lifestyle also matter, so treat the result as a guide.