By Jon Bastian

Ask most people how to determine a dog’s age in human years, and they’ll probably say, “Multiply by seven.” However, this method is inaccurate, and more so the older a dog gets. For a twelve year-old dog, the result could be off by over twenty years. Multiplying by seven only comes close while a dog is four and a half years old.

Dogs mature faster than humans, reaching the equivalent of twenty-one years in only two, but then aging slows to an average of four human years every year after. Dogs under thirty pounds live longest, often well into their teens; dogs over a hundred pounds have the shortest lifespans, being considered not just old but geriatric by six or seven.

So, next time someone asks you a dog’s age in human years, you’ll know how to give a more accurate answer. Subtract two from the age, multiply that by four and add twenty-one. After all, a forty-five year-old wouldn’t appreciate their spouse telling everyone that they’re fifty-six. You shouldn’t do the same to your eight year-old pooch.

So, now that you know better. How old is your dog in human years? Share in the comments.