Why Dogs Sleep With Their Tongue Out: Relaxation or Anatomy?

Norwich Terrier sleeping peacefully on a soft blanket with its eyes closed and a small pink tongue sticking out.

Your dog claims his favorite chair, turns around twice, gives one enormous sigh, and melts into the cushions as though the day has been absolutely exhausting.

Usually, that little tongue peeking out is just relaxation meeting anatomy: the jaw and lips loosen during sleep, and the way your dog’s mouth is built helps determine how much tongue escapes.…