How old is 3 in dog years?

This is a bit of a trick question! There's no one-size-fits-all answer for how old a human age is in "dog years". Here's why:

* Early Development is Fast: The first year of a dog's life is roughly equivalent to 15 human years.

* Slowing Down: After the first year, each dog year is roughly equivalent to 4-5 human years.

* Breed Differences: Smaller dog breeds tend to live longer than larger breeds.

So, 3 human years wouldn't be a straightforward conversion. It's more accurate to think of a 3-year-old human being roughly equivalent to a young puppy.