Kathleen Genevieve Ledecky (; Czech pronunciation: ['l?d?tski?]; born March 17, 1997) is an American competitive swimmer.
She has won five Olympic gold medals and 15 world championship gold medals, the most in history for a female swimmer.
She is the current world record holder in the women's 400-, 800-, and 1500-meter freestyle (long course).
She also holds the fastest-ever times in the women's 500-, 1000-, and 1650-yard freestyle events.
In her international debut at the 2012 London Olympic Games as a 15-year-old, Ledecky unexpectedly won the gold medal in the women's 800-metre freestyle.
Four years later, she left Rio de Janeiro as the most decorated female athlete of the 2016 Olympic Games with four gold medals, one silver medal, and two world records.
In total, she has won 34 medals (28 golds, 5 silvers, and 1 bronze) in major international competitions, spanning the Summer Olympics, World Championships, and Pan Pacific Championships.
During her career, she has broken fourteen world records.
Ledecky's success has earned her Swimming World's Female World Swimmer of the Year a record-breaking five times.
Ledecky was also named Associated Press Female Athlete of the Year in 2017, international female Champion of Champions by L'Équipe in 2014 and 2017, United States Olympic Committee Female Athlete of the Year in 2013, 2016 and 2017, and Sportswoman of the Year by the Women's Sports Foundation in 2017.
Ledecky's 11 individual gold medals at the World Aquatics Championships and 15 combined individual titles at the Olympics and World Aquatics Championships are records in women's swimming.