Winner of multiple gold medals, Daiya Seto is a professional swimmer from Japan. He specializes in individual medley, butterfly, breaststroke, and freestyle competitions. At the 2012, 2014, 2016, 2018, and 2021 world short course championships, as well as the 2013, 2015, and 2019 world long course championships, he won the gold medal in the 400-meter individual medley. In the 200-meter short course butterfly and the 400-meter individual medley, Seto has set world records.

When Seto was five years old, he started swimming. When he placed third in the 200- and 400-meter individual medley events at the national selection competition, he just missed making the 2012 Japan Olympic Team. At the 2012 FINA Swimming World Cup, where he participated in all of the competitions, he lowered his times and finished in fourth place overall. At the 2012 World Short Course Championships, he finished the short course season for the year. Here, Seto earned his first career international medals. He initially raced in the 400-meter individual medley, where he won his first world championship in a time that set a new Asian record and was over a second and a half quicker than László Cseh, who came in second. The 200-meter individual medley was his next event, and in a sprint, he beat Cseh to win the silver medal in 1:52.80.

Seto won the highest-scoring male award and prize money at the Doha, Qatar, stop of the 2021 FINA Swimming World Cup. His victories in the 200-meter breaststroke and 400-meter individual medley on the third and final day of competition in Doha contributed to his high overall score. Seto’s official status as a professional swimmer was declared by SwimSwam on the same day he was named the male overall champion for the Doha stop.