When most people convert dog years to human years they use a basic formula (1 dog year = 7 human years), however there is a more advanced formula. The advanced formula says the first 2 dog years are equal to 10.5 human years each, after that each dog year is equal to 4 human years.

Ignoring all the mathematics... This utility uses both formulas AND converts human year to dog years, as well as dog years to human years!