|Date||26 – 28 July 2021|
|Location||Olympic Aquatics Centre, 2-1, 2chome, Tatsumi, Koto-ku, Tatsumi-no-Mori Seaside Park, Tokyo, Japan|
|Participants||27 from 20 countries|
Hungary’s Katinka Hosszú had dominated the individual medleys at Rio in 2016, winning gold in both the 200 and 400 IM, the latter in world record time. She had since won the 2017 World Championship, the 2018 European Championship, and the 2019 Worlds, but she came to Tokyo at 32-years-old and had not posted the fastest times of the year. Her biggest challengers were expected to be Americans Alex Walsh and Kate Douglas, who both swam for the University of Virginia, and Britain’s Abbie Wood, who had the second fastest time on the year. Also considered was Japan’s Yui Ohashi, the 2018 Pan Pacific Champion in both IMs and a silver medalist at this event at the 2017 Worlds, who had already won the 400 IM in Tokyo.
Douglas was the fastest qualifier in both the heats and semi-finals as all the favorites made it to the final. The final was led for 100 metres by China’s Yu Yiting but she dropped back on the breaststroke and freestyle legs and would finish fifth. Ohashi was second after the butterfly and breaststroke legs, trailing Walsh into the final freestyle lap, but the Japanese would finish the fastest to take gold narrowly over the American, as Douglas gave the USA two medals by finishing third, only 11 hundredths ahead of Wood. Hosszú was never a factor and finished seventh.
|22||Viktoria Zeynep Güneş||TUR||–|