The greatest reliable age recorded for a dog is 29 years 5 months for an Australian cattle-dog named Bluey, owned by Les Hall of Rochester, Victoria, Australia. Bluey was obtained as a puppy in 1910 and worked among cattle and sheep for nearly 20 years before being put to sleep on 14 November 1939.

Most dogs live for 8–15 years, and authentic records of dogs living over 20 years are rare and generally involve the smaller breeds.