12 dog years in human years
≈ 74 human years for a medium breed. Size changes the answer a lot:
| Small (under 20 lb / 9 kg) | 64 human years |
|---|---|
| Medium (21–50 lb / 10–23 kg) | 74 human years |
| Large (51–100 lb / 23–45 kg) | 84 human years |
| Giant (100 lb+ / 45 kg+) | 104 human years |
At 12 years your dog is into senior territory for most breeds. Senior status starts around age 6 for giant breeds, 8 for large, 10 for medium and 11 for small ones — see the life stage chart.
Part-way through year 12 (medium breed)
| 12 yr 0 mo | 74 human years |
|---|---|
| 12 yr 3 mo | 75 human years |
| 12 yr 6 mo | 77 human years |
| 12 yr 9 mo | 78 human years |