The heaviest dog ever recorded was Zorba, an English mastiff from the United Kingdom that weighed in at 343 pounds. He measured 8.25 feet in length from nose to tail and stood 35 inches tall.
Zorba was listed in the 1989 Guinness Book of Records, but Guinness stopped recording records for large and heavy pets in 2000.
As of November 2014, a Great Dane named Giant George holds the record for the tallest dog and the tallest living dog ever. He stands a full 43 inches tall and lives in Tucson, Arizona.
The largest wild dog ever recorded was the Epicyon haydeni, or Hayden's bone-crushing dog. This now-extinct dog lived during the mid-late Miocene epoch in North America and weighed an estimated 374.8 pounds.