Video: Guinness World Records 2013: US Great Dane is planet's tallest dog The Great Dane, who towers 2.2m (7ft 4") on his hind legs, has been named the tallest dog ever recorded in the latest Guinness Book of World Records launched on Thursday. Measuring 1.12m from paw to withers - the point between the shoulder blades at which the official height of a four-legged mammal is judged - Zeus is officially the tallest dog in the world, the volume claims. Guinness World Records 2013 says the towering hound breaks the record of Giant George, another Great Dane who is one inch shorter. "The most common thing people ask is: 'Is that a dog or a horse?'" says the three-year-old's owner Denise Doorlag.