Dynaformer (April 1, 1985 – April 29, 2012) was a thoroughbred stallion, who stood at stud at Three Chimneys Farm in Kentucky. He was retired on 14 April 2012 after suffering an aortic valve rupture while in his stall. He was euthanised on April 29 at age 27, 9 years to the day after the birth of his Kentucky Derby winning son Barbaro. He was sired by Epsom Derby winner Roberto out of Andover Way (by His Majesty).