Why Do Dogs Sleep So Much?

Really, it depends on the breed, but on average? They do sleep more than humans do,

On average, dogs have been known to sleep 12 to 14 hours a day, though puppies might sleep for up to 19 hours.

Like with humans, older dogs sleep more because life becomes more difficult to live, and puppies sleep so much because like human children, they expend a ton of energy when playing and exploring.

None of this is surprising; statistically, carnivores need to sleep more than omnivores such as humans, because carnivores don't need to spend as much time eating to gain energy from their food.

However, dogs can sleep too much.  If your pooch is sleeping all day, and not just for roughly 14 hours it's possible that your dog has canine depression, and it is advised that you contact your vet.