|Date||28 – 30 July 2021|
|Location||Olympic Aquatics Centre, 2-1, 2chome, Tatsumi, Koto-ku, Tatsumi-no-Mori Seaside Park, Tokyo, Japan|
|Participants||51 from 42 countries|
The defending champions were Canada’s Penny Oleksiak and American Simone Manuel, who had shared gold at Rio in 2016. Oleksiak was back but Manuel, also the 2019 World Champion, had not made the US team in this event. Oleksiak made the final along with the Australian duo of Emma McKeon and Cate Campbell and Sweden’s Sarah Sjöström and the medals were expected to be contested by those three.
McKeon had qualified fastest, setting an Olympic record of 52.13 in the heats. She also qualified fastest in the semi-finals, trailed in both the heats and semi-finals by the relatively unheralded Siobhán Haughey from Hong Kong, China.
In the final McKeon was out of the blocks the quickest (0.58 reaction time) and had a narrow lead at the turn over Haughey – 25.08 to 25.10. Campbell was in third at 50 metres while Oleksiak and Sjöström were well back, next-to-last and last. McKeon pulled away on the final lap, winning comfortably in an Olympic record 51.96, but Haughey held on for silver in 52.27. Campbell took bronze, head of the fast-closing Oleksiak (fourth) and Sjöström (fifth).
For McKeon this was her fourth medal of the Tokyo 2020 Olympics, having helped Australia win gold in the 4 x 100 free relay, and adding bronze medals in the 100 butterfly and the 4 x 200 freestyle relay. She was not done. By Games end, McKeon would have seven medals and four gold medals, equaling Soviet gymnast Mariya Gorokhovksaya, the only other women to win seven medals at one Olympics, at Helsinki back in 1952. McKeon’s four golds in Tokyo would also equal 11 other women who had done that at one Olympics, trailing only East German swimmer Kristin Otto, who won six golds at Seoul in 1988.
|36||Quah Ting Wen||SGP||–|
|40||Mia Blazhevska Eminova||MKD||–|
|43||María Victoria Schutzmeier||NCA||–|