In 2019, UC San Diego researchers published a landmark epigenetic study revealing the accurate formula is human age = 16 × ln(dog age) + 31. Dogs age extremely rapidly in year one then slow considerably.
Our calculator applies this formula then adjusts for breed size — a 7-year-old Chihuahua and Great Dane are in completely different life stages.
human_age = 16 × ln(dog_age) + 31. Size offsets: Small −2 to −5 yrs. Large +2 to +5 yrs. Giant +5 to +12 yrs.
| Dog Age | 🐩 Small | 🐕 Medium | 🪶 Large | 🐻 Giant |
|---|---|---|---|---|
| 1 yr | 15 | 15 | 15 | 15 |
| 2 yrs | 24 | 26 | 27 | 29 |
| 3 yrs | 28 | 31 | 33 | 36 |
| 5 yrs | 36 | 40 | 43 | 50 |
| 7 yrs | 44 | 50 | 55 | 63 |
| 10 yrs | 56 | 62 | 68 | 79 |
Find your dog's exact daily calorie needs using the vet RER formula.
Calculate Calories →Always confirm significant health changes with your veterinarian.