1. Saint Bernard
The Saint Bernard dog generally has large head. The longest/biggest recorded dog's height was 42 inches (107 cm), 35 inches (89 cm) at the shoulders, and length was 102 inches (2.59 m) weighed 220 lb (100 kg). Saint Bernard breed's average weight is between 140 and 264 lb (64–120 kg) or more and height is 27½ inches to 35½ inches (70 to 90 cm).
2. English Mastiff
Also Known as Mastiff or Old English Mastiff is the second biggest dog. An English Mastiff named Hercules was put in the Guinness World Book of Records for weighing in at 282 pounds in 2001. Height of this breed dogs are 30 Inches (76 cm.) at the shoulder, A typical weight could be 150–250 pounds (68–110 kg).An English Mastiff from the UK, named "Aicama Zorba of La Susa" weighed in at 338 pounds and measured almost 8.25 feet long from nose to tail and holds the title as the world's largest dog.
3. Neapolitan Mastiff
Neapolitan Mastiff also known as Italian Mastiff and Mastino Napoletano which is third biggest dog breed in the world. The average weight for this breed is up to 170 pounds (70 kg) to 200 pounds (90 kg). Their height ranges between 26–31 inches (66–79 cm) at the withers.
4. Newfoundland
Newfoundland is forth biggest dog breed; famously known for their giant size and tremendous strength, sweet dispositions, and loyalty. Average weight of this dog breed is 60-70kg (132 to 154 pounds). Their height ranges between 22–28 inches tall at the shoulder.
5. Dogue de Bordeaux
This fifth largest dog breed Also known as Bordeaux Mastiff or French Mastiff or Bordeauxdog; this breed of dogs are strong, powerful, and imposing.
Average weight of this dog breed is 65 kg (145 Pounds) and their shoulder height ranges between 23-30 inches.
6. Presa Canario
Perro de Presa Canario is a large Molosser-type dog breed with average weight of 59 kg (130 pounds) and shoulder height ranges between 21 - 25 inches. This is sixth biggest dog.
7. Irish Wolfhound
Irish Wolfhound is seventh biggest dog with average weight of 46–70 kg (101–154 lbs). Generally breeders aim for a height range of 85 to 95 centimeters (34 to 38 inches) at the withers.
8. Great Dane
Great Dane breed is known as eight biggest dogs and is one of the world's tallest dog breeds. Current world record with measuring 109 cm (43 in) from paw to shoulder; 220 cm (7.2 ft) from head to tail, is George. Average weight of Great Dane breed is up to (54.5 kg) 120 pounds.
9. Great Pyrenees
Great Pyrenees is also known as Pyrenean Mountain Dog is ninth largest dog. Average weight of this breed is up to (54.5 kg) 120 pounds and shoulder height ranges between 27 - 32 inches.
10. Kuvasz
Hungarian origin Kuvasz breed is 52.3 kg (115 Pounds) in weight and shoulder height ranges between 28 - 30 inches.
Source - World Records
