What is the biggest dog?

The largest dogs are Great Danes and certain types of Mastiffs. Saint Bernards, Great Pyrenees and Irish Wolfhounds are also some of the biggest dog breeds.

The largest dogs often weigh more than 100 pounds as adults, and some breeds can exceed 200 pounds. These breeds are usually quite tall, such as the 30 inch Great Dane and the 34 inch Irish Wolfhound. Such breeds were originally bred for hunting and fighting. The Great Pyrenees herded and guarded sheep, and the Neapolitan Mastiff acted as a guard animal. Larger dogs generally require more space and have a higher upkeep cost due to their appetite.