The biggest dog in the world can be measured by weight or by height, so here is the breakdown:

Among the two heaviest breeds in the world are the Saint Bernard weighing in between 72 and 110 kilos and the English Mastiff whose weight can be over 91 kilos. The Guinness Book of World Records notes one English Mastiff by the name of Zorba who weighed nearly 143 kilos (better get a second couch for him!)

The tallest breed of dog in the world is a tie between the Irish Wolfhound whose average height is 90 cm at the shoulder, and the Great Dane who stands at between 76 and 100 cm.

It is a comfort to know, however that, for the most part, the temperament of the these man-sized dogs is quite good. Great Danes are known to be friendly, gentle, good with people (including kids) and other dogs. Irish Wolfhounds are known to be good natured, gentle, intelligent and good with children. English Mastiffs are known as loyal, devoted family dogs and make good guard dogs. They are generally gentle and good natured unless someone poses an immediate threat to their family.

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