Kieran Smith (born May 20, 2000) is an American swimmer specializing in freestyle and individual medley events.

[9] At the 2018 FINA World Swimming Championships in Hangzhou, China in December 2018, Smith placed 13th in the prelims heats of the 400-meter individual medley with a 4:08.52.

[16] During his junior year with the Florida Gators, Smith tied his American record in the 500-yard freestyle, swimming a 4:06.32 at the 2021 Southeastern Conference Championships.

[36] A crowd of about 70 people welcomed Smith back to his hometown of Ridgefield, Connecticut following the Olympic Games in a Meet and Greet format after his parents had a car pick him up from the airport so they could surprise him when he arrived at the house.

[44] Smith entered to compete in the 200-meter individual medley, 200-meter freestyle, 400-meter individual medley, and 400-meter freestyle at the 2021 World Short Course Championships in Abu Dhabi, United Arab Emirates in December, and the announcement of the United States team, including Smith, for the Championships was the number two item on the Swimming World honor of "The Week That Was" for the week of November 1, 2021.

[51] For his second final of the evening, Smith placed sixth in the 200-meter individual medley with a personal best time of 1:53.76.

[52] Day two, Smith swum a personal best time of 1:42.64 in the 200-meter freestyle to win his heat in the prelims and advance to the final ranking fourth.

[53] In the final, Smith placed fifth with a time of 1:42.29, finishing two-hundredths of a second behind fourth-place-finisher Duncan Scott of Great Britain.

[56][57] Later in the same finals session, Smith led-off the 4×200-metre freestyle relay in 1:41.79, helping win the gold medal and set a new American record in the event at 6:47.00.

[65] In the evening, Smith split a 18.77 on the 4×50-yard freestyle relay in the final, helping achieve a win in a new meet record time of 1:15.18.

[72] For his final event, Smith anchored the 4×100-yard freestyle relay to a first-place victory in 2:46.91, splitting a time of 41.31 seconds.

[73] Smith won a total of two individual titles and four relay titles, earned 92 individual points, and helped the Florida Gators achieve a Southeastern Conference Championships victory that was 476 points ahead of the second-place teams, which marked the largest winning margin in the history of the Southeastern Conference Championships.

[85] On the first day of the 2022 US International Team Trials in Greensboro, North Carolina, Smith swam a personal best time of 48.50 seconds in the preliminary heats of the 100-meter freestyle to qualify for the final ranking fifth.

[88] He won the final with a time of 1:45.25, qualifying in the event, as well as the 4×200-meter freestyle relay, for the 2022 World Aquatics Championships team.

[89] Day four, he ranked fourth in the morning prelims heats of the 400-meter freestyle with a 3:50.72 and qualified for the evening final with a time less than half a second slower than the first-ranked swimmer.

[93] Beginning his competition on the first day of pool swimming at the 2022 World Aquatics Championships, Smith ranked fifth in the prelims of the 400-meter freestyle, qualifying for the final.

[96] In the evening semi-finals, he dropped over half a second off his prelims time, swimming a 1:46.06 to qualify for the final ranking eighth.

[100][101][102] On October 21, at the first stop of his first FINA Swimming World Cup, 2022 FINA Swimming World Cup stop in Berlin, Germany, Smith won a silver medal in his first event, the 400-meter freestyle, with a personal best time of 3:37.27, which was less than one second slower than gold medalist Matthew Sates of South Africa.

[106] Day one in Indianapolis for the third and final stop, Smith won a gold medal in the 400-meter freestyle with a new US Open record and personal best time of 3:35.99, which was 1.51 seconds faster than silver medalist Danas Rapšys of Lithuania.

[109] For his first race of the evening session, he won the gold medal in the 200-meter individual medley with a personal best time of 1:52.98.

[128][129] Legend: h – prelims heat; r — relay 1st leg The following medals Smith has won at Swimming World Cup circuits.