For a long time, it has been thought that to calculate the age of a dog in human age the only thing that had to be done was to multiply the years of the animal by seven. However, this calculation is not so simple and we can say that in this way the result is quite inaccurate.
Why is it not so simple to calculate the age of a dog?
The age of a dog in its human equivalent has to do with other factors such as size or race. Also influencing issues such as the development phase of the animal : time does not pass as fast during the first years of development as when the dog is already an adult.
In this way, experts indicate how in the first year of life the dog can reach an equivalent of up to 15 years of human age . Meanwhile, the second year only equals 9 human years, and in adulthood each year the dog equals four years of a human being .
Regarding the race and the size they can affect in the following way:
We can say that when the dog turns 5 years old it is the moment in which the size of the dog begins to matter to calculate the age. According to the specialist Stanley Coren, a writer with more than 40 books dedicated to dogs, small breeds age 4 years for each one that passes; the medium 6 years and the large races 7 or 8 years.