Count Fleet was born and died at Stoner Creek Stud farm in Paris, Kentucky, United States. He was a Thoroughbred racehorse and Triple Crown champion in 1943. Sired by 1928 Kentucky Derby winner Reigh Count and out of a mare named Quickly, Count Fleet was owned by the wife of John D. Hertz (1879-1961), best known for the rental car company bearing his name. John Hertz initially did not think much of Count Fleet and contemplated selling him until jockey Johnny Longden convinced him to keep the colt.
Trained by Don Cameron and ridden by future Hall of Fame inductee Longden, as a two-year-old Count Fleet started off slowly, losing several times before getting his first win. He gained respect with his six-length victory in the Champagne Stakes, in which he set a new track record, then followed this up by beating the best horses in the country in the Pimlico Futurity, where he equaled the track record. In the Walden Stakes, he ran away from the field, winning by more than thirty lengths. At season's end, he had won 10 of his 15 races while never being out of the money, a performance that earned him the two-year-old championship honors.
As a three-year-old, Count Fleet dominated North American racing, never losing a race. Leading up to the Kentucky Derby, he won the important Wood Memorial but injured himself in the process. He recovered to take the United States' most prestigious race by three lengths, then went on to Baltimore, Maryland, where he dominated the Preakness Stakes, taking that one by eight lengths. He won the Withers Stakes before heading to Elmont, New York for the Belmont Stakes where he captured the Triple Crown by scoring a 25-length victory, a record margin that stood until 1973. When the season ended, Count Fleet was voted Champion Three Year Old and named American Horse of the Year.
Rather than risk serious injury, Count Fleet did not race as a four-year-old after it was discovered that he had injured his leg. He was retired to stud having won 16 of 21 races and went on to enjoy great success as a sire. His offspring numbered 38 stakes winners, including Kentucky Derby winner Count Turf, Belmont Stakes winners Counterpoint and One Count, Horse of the Year champions, and a Champion Three Year Old Filly. Count Fleet's daughters produced superhorse Kelso, 1965 Kentucky Derby winner Lucky Debonair, the Canadian star filly Ice Water, and multiple Grade I stakes winner Tompion. Another daughter, Sequence, mated with 1955 Preakness and Belmont winner Nashua to produce Gold Digger, dam of the influential modern sire Mr. Prospector.
In 1961, Count Fleet was inducted in the National Museum of Racing and Hall of Fame.
Count Fleet died on December 3, 1973 and was buried at Stoner Creek farm in Paris, Kentucky.
In the Blood-Horse magazine ranking of the top 100 U.S. thoroughbred champions of the 20th Century, Count Fleet was ranked #5.