Mollie O’Callaghan was born in Queensland and is 18 years of age. She began swimming at the age of four and entered her first competition three years later.

Mollie’s international career began in 2019, when at age 15, she took part in the World Championships in Budapest, Hungary for the Australian national team. At the World Championships she won a silver medal in the women’s 400m freestyle relay.

At the 2020 Queensland Short Course Championships, Mollie set the new national 16 years age group record in the 100m freestyle with a time of 52.10. Mollie also dominated the backstroke events, winning gold in 50/100/200m events.

At the 2020 Tokyo Olympics, Mollie brought home two gold medals and a bronze at only 17 years old – the youngest member of the squad. Mollie swam in the heats of the 4 x 100m freestyle relay (gold), 4 x 100m medley relay (gold), and the 4 x 200m freestyle relay (bronze).

The 2022 Australian Championships saw Mollie become the first women to go sub 53 seconds in the 100m freestyle event in 2022. She then beat this in the final with a new personal best time of 52.49. Mollie went on to qualify for five individual World Championship events.

At the 2022 World Championships, Mollie began with the 4 x 100m freestyle relay where she led the team and helped secure first place. Mollie also swam in the 4 x 200m freestyle relay where they came second behind the USA. At the end of the Championships Mollie swam in the individual 100m freestyle event where she won gold.

The Commonwealth Games in Birmingham was another chance for Mollie to show the world what she has. At the Games she shone – taking home five gold medals and two silvers. She was part of four gold medal winning relay teams, including the world record 4 x 200m freestyle team, and the gold medal in Swimming’s blue ribbon event – the 100m Freestyle.