🐶 Dog Age Calculator
Convert between dog years and human years with this scientifically-based calculator.
Human to Dog Age
Convert human years to dog years
Dog Size Overview
Small Dogs
up to 9 kg • Chihuahua, Yorkshire Terrier, Pomeranian
Medium Dogs
9.5-22.5 kg • Beagle, Cocker Spaniel, Border Collie
Large Dogs
23-41 kg • Labrador, German Shepherd, Boxer
Giant Dogs
over 41 kg • Great Dane, Saint Bernard, Newfoundland
How Dog Age Calculation Works
Converting a dog’s age to human years is more nuanced than the old “multiply by 7” rule. Dogs mature much faster in their early years, and aging rates vary by size and breed:
- The first year of a dog’s life is roughly equal to 15 human years for small and medium breeds, and slightly less for large breeds.
- The second year adds about 9 more human years.
- After that, each additional dog year equals about 4 to 7 human years, depending largely on the dog’s size:
- Smaller dogs age more slowly and tend to live longer
- Larger dogs age more quickly and often have shorter lifespans
That's why our calculator takes your dog's size into account—to give a more personalized and accurate estimate. Keep in mind that these are general approximations; factors like breed, health, and lifestyle also play a role in how dogs age.
Did You Know?
- The oldest dog on record lived to be 29 years old (about 140 in human years).
- Small dogs can live twice as long as giant breeds on average.
- Dogs experience similar age-related changes to humans, like gray hair and joint issues. However, they do not have the same sensitivity to heat or cold.