Born in Dunedin, Caitlin Deans began swimming in learn-to-swim lessons, where her talent was quickly spotted. She joined Waves Swim Club and later Neptune Swim Club after Waves dissolved, developing a love for distance freestyle. Deans has fond memories of racing at junior nationals at the old QEII pool in Christchurch and the excitement of finishing racing so she could play on the hydro slides.

In 2015, Deans made her first junior national team when she competed at the Australian State Teams Short Course in Canberra.

Deans made her senior international debut at the 2018 Oceania Swimming Championships in Papua New Guinea, winning six medals. That same year, she competed at the FINA World Swimming Championships (25m) in China, where she placed tenth in the 4x200m freestyle relay and 15th in the 800m freestyle.

Her breakthrough came at the 2022 New Zealand Championships, qualifying for her first Aquablack team with a FINA 'A' time in the 1500m freestyle. At the 2022 World Aquatics Championships in Budapest, she made the final in the 4x200m freestyle relay (7th) and placed 13th individually in the 1500m. 

Deans represented New Zealand at the 2022 FINA World Swimming Championships (25m) in Melbourne, where she placed fifth in the 1500m freestyle and lowered her best time by over ten seconds. She also placed 19th in the 200m freestyle and was part of the 4x200m freestyle relay that placed eighth.

At the 2023 World Aquatics Championships, Deans again competed in the 1500m and 4x200m freestyle events, with a best finish of eleventh place in the latter event. That same year, she competed at the World Aquatics Swimming World Cup, earning a bronze medal in the 1500m freestyle in Athens.

Deans swam her way to a new personal best time in the 1500m freestyle at the 2024 World Aquatics Championships, placing tenth. She was then called up to the 4x200m freestyle relay final, where she helped the team reset the New Zealand record on the way to a fifth place finish.

At the 2024 New Zealand Swimming Championships, Deans placed third in the 200m freestyle, earning herself a berth on the 4x200m freestyle relay at the Paris 2024 Olympic Games. Becoming an Olympian is a childhood dream come true for Deans, who says its still feels 'surreal'.

Deans came away from Paris 2024 as an Olympic finalist, making history as part of the part of the women's 4x200m freestyle relay by becoming the first group of Kiwi women to progress through to a relay final at an Olympic Games. The quartet of Deans, Erika Fairweather, Eve Thomas, and Laticia Transom placed eighth in the final.

She trains with Swim Dunedin under coach Lars Humer and draws daily inspiration from her teammates. Outside the pool, Deans holds a Bachelor of Science in Physiology from the University of Otago and works at a biotech company.

Favourite quote - “Don’t compare your life to others. There’s no comparison between the sun and the moon. They both shine when it’s their time.”