Use the common estimate: dog age in human years = 15 for the first year, 9 for the second year, and about 5 for each additional year
For a quick estimate: human age = 15 + 9 + 5 × (dog age in years – 2)
For dogs under 1 year old, compare by months instead of years
For a more accurate result, use breed size and weight, since smaller dogs usually age more slowly than larger dogs
Use veterinary age charts for the most accurate dog-to-human age conversion
Consider that health, breed, and genetics can affect aging rate
Calculate the dog’s age in actual years first, then convert it using an age chart or formula