Size and Measurement

The height of horses is measured at the highest point of an animal's withers, where the neck meets the back. This point was chosen as it is a stable point of the anatomy, unlike the head or neck, which move up and down.

The English-speaking world measures the height of horses in hands (abbreviated "h" or "hh", for "hands high") and inches. One hand is equal to 101.6 millimeters (4 inches), and one inch is equal to 25.4 millimeters. The height is expressed as the number of full hands, followed by a decimal point and the number of additional inches. Thus a horse described as "15.2 h", is 15 hands, 2 inches (160 centimeters, or 62 inches) in height.

The size of horses varies by breed, but can also be influenced by nutrition. Light riding horses such as Arabians, Morgans, or Quarter Horses usually range in height from 14 to 16 hands (56 to 64 inches, 142 to 163 cm) and can weigh from 380 to 550 kilograms (840 to 1,200 lb). Larger riding horses such as Thoroughbreds, American Saddlebreds, or Warmbloods usually start at about 15.2 hands (62 inches, 157 cm) and often are as tall as 17 hands (68 inches, 173 cm), weighing from 500 to 600 kilograms (1,100 to 1,300 lb). Heavy or draft horses, such as the Clydesdale, Belgian, or Shire, are usually at least 16 tp 18 hands (64 to 72 inches, 163 to 183 cm) high and can weigh from about 700 to 1,000 kilograms (1,500 to 2,200 lb).

The largest horse in recorded history was probably a Shire horse named Mammoth, who was born in 1848. He stood 21.2½ hands high (86.5 in/220 cm), and his peak weight was estimated at 1,500 kilograms (3,300 lb). The current record holder for the world's smallest horse is Thumbelina, a fully mature miniature horse affected by dwarfism. She is 17 inches (43 cm) tall and weighs 27 kilograms (60 lb).

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