The average horse stands around 16 hands high, which is roughly 64 inches (5 foot 4 inches) tall. The height of any individual horse depends on a number of factors, including the lineage of the horse and its breed.
Generally, the height of a horse's parents is a good indicator of how tall the horse will be when it's grown, although genetics is not a sure bet when estimating the horse's potential height. The smallest horse on record stood just 15 inches tall. The Guinness Book of World Records states that the tallest horse recorded is a 1850 Shire gelding by the name of Sampson. This horse measured 21.5 hands,which is 86.5 inches tall.