Adam Rainer (1899 – 4 March 1950) is the only person in recorded history to have been both a dwarf and a giant.

Rainer was born in Graz, Austria-Hungary. In 1917, at age 18, he was measured at 122.55 cm (4 ft 0.25 in). A typical defining characteristic of dwarfism is an adult height below 147 cm (4 ft 10 in). Then, likely as a result of a pituitary tumor, he had a dramatic growth spurt so that by 1931 he had reached a height of 218 cm (7 ft 2 in). As a result of his gigantism he became bedridden for the rest of his life. When he died in 1950 he had reached a height of 234 cm (7 ft 8 in). His feet measured 33.3 cm (13.1 inches), and his hands 23.9 cm (9.4 inches). He weighed 109 kg (241 pounds).