Kathleen Genevieve Ledecky is an American competitive swimmer. She has won seven Olympic gold medals and 21 world championship gold medals, the most in history for a female swimmer. She has won a world record 16 individual gold medals at the World Aquatics Championships. Ledecky's seven individual gold medals at the Olympics and 26 overall medals at the World Aquatics Championships are records in women's swimming. Ledecky is the world record holder in the women's 800- and 1500-meter freestyle as well as the former world record holder in the women's 400-meter freestyle. She also holds the fastest-ever times in the women's 500-, 1000-, and 1650-yard freestyle events. She is widely regarded as the greatest female swimmer of all time and one of the greatest Olympians of all time.