Fairweather became New Zealand's first gold medallist at a World Aquatics Championships when she was crowned world champion in the Women's 400m freestyle in 2024. It was a monumental competition for the 20-year-old, who also picked up silver and bronze in the 200m and 800m freestyle events. She will contest all three events at the Paris 2024 Olympic Games, in addition to the 4x200m freestyle relay.

Seven months earlier, Fairweather became the fifth woman in history to break the four-minute barrier in the 400m freestyle at the 2023 World Aquatics Championships, where she claimed bronze in the event amongst a star-studded field of athletes. Speaking of the achievement, Fairweather said: “I’ve sort of gained a new sense of confidence in my ability,” said Fairweather.“Going into Worlds I didn’t back myself to be in the medals to be honest, I was thinking I could make a final but I’d be going for 4th, 5th, 6th. Now going forward I think that was a giant mistake, I think I should be reaching higher.”

Fairweather has represented New Zealand in the pool since age 14, when she made her international debut at the Junior Pan Pacific Championships in Fiji. In the same year, Fairweather was the youngest competitor at the Youth Olympic Games in Buenos Aires.

Just a year later, Fairweather made her first senior international team by qualifying for the 2019 FINA World Aquatics Championships in Gwangju, where she contested two individual events and led off the women's 4x200m freestyle relay to a tenth-place finish. Fairweather became World Junior Champion at the 2019 World Junior Swimming Championships in Budapest, claiming gold in the 200m freestyle. 

Her first Olympic Games were Tokyo 2020, where, at age seventeen, she was a finalist in the 400m freestyle and a semi-finalist in the 200m freestyle. Fairweather broke Lauren Boyle's longstanding New Zealand record in the 400m freestyle to earn her spot in the final. 

In 2022, Faiweather competed at the FINA World Aquatics Championships where she was a finalist in the 400m freestyle and the 4x200m freestyle, in addition to being a semi-finalist in the 200m freestyle. She then went on to compete at her first Commonwealth Games in Birmingham, where she placed fourth in the 400m freestyle and fifth in the 200m freestyle.

Fairweather earned her first senior international medals at the 2022 FINA World Swimming Championships (25m), claiming two silvers in the 400m and 800m freestyle events and helping the women's 4x50m and 4x200m freestyle relay to finals appearances.

Fairweather is born and bred in Dunedin and trains under the guidance of Swim Dunedin's Lars Humer.

🥇 2024 World Aquatics Championships - 400m freestyle

2024 World Champion in the women's 400m freestyle (3:59.44)

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🥇 2019 FINA World Junior Swimming Championships - 200m freestyle

2019 World Junior Champion in the women's 200m freestyle (1:57.96)

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🥇 2023 World Aquatics Swimming World Cup - 3x gold medallist in the 400m freestyle

2023 400m freestyle Triple Crown winner, in addition to five other podium finishes at the World Aquatics Swimming World Cup.

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🥈 2024 World Aquatics Championships - 200m freestyle

2024 World Aquatics Championships silver medallist in the 200m freestyle (1:55.77)

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🥈 2022 FINA World Swimming Championships (25m) - 400m freestyle

2022 FINA World Swimming Championships (25m) silver medallist in the 400m freestyle (3:56.00)

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🥈 2022 FINA World Swimming Championships (25m) - 800m freestyle

2022 FINA World Swimming Championships (25m) silver medallist in the 800m freestyle (8:10.41)

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🥉 2024 World Aquatics Championships - 800m freestyle

2024 World Aquatics Championships bronze medallist in the 800m freestyle (8:22.26)

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🥉 2023 World Aquatics Championships - 400m freestyle

2023 World Aquatics Championships bronze medallist in the 400m freestyle (3:59.59)