The women's 100 metre backstroke event at the 2020 Summer Olympics was held from 25 to 27 July 2021 at the Tokyo Aquatics Centre. It was the event's twenty-third consecutive appearance, having been held at every edition since 1924. An unusual occurrence happened where the Olympic record for this event was broken three times in a single day and five times through the course of the entire competition.

Summary Australia's world record holder Kaylee McKeown broke the Olympic record to win her first individual Olympic title in 57.47, just 0.02 seconds off her world record. Third at the turn, McKeown used a blistering back half to overtake the field and become Australia's first Olympic champion in this event. While Canada's defending Bronze medallist Kylie Masse led at the halfway mark, she could not withstand McKeown's late charge, touching for silver in 57.72 - only 0.02 seconds off her national record. U.S.' previous world record holder Regan Smith was unable to replicate her time from the heats and semi-finals, settling for bronze in 58.05. Though Smith's teammate Rhyan White (58.43) was second at the turn, she would fade over the final 50 m to take fourth place. Australia's Emily Seebohm (58.45), the 2012 silver medallist, was out-touched by 0.02 seconds to finish fifth.

Meanwhile, Great Britain's Kathleen Dawson could not repeat her stunning 58.01 swim from the European Championships months earlier, placing sixth. Dutch record holder Kira Toussaint also missed her national record from the Eindhoven Qualification Meet to take sixth. Israel's Anastasia Gorbenko came eight in 59.90, missing her personal best time from the semi-finals by 6 tenths of a second.

Records Prior to this competition, the existing world and Olympic records were as follows.

The following records were established during the competition:

Date Event Swimmer Nation Time Record July 25 Heat 4 Kylie Masse 58.17 July 25 Heat 5 Regan Smith 57.96 July 25 Heat 6 Kaylee McKeown 57.88 July 26 Semifinal 1 Regan Smith 57.86 July 27 Final Kaylee McKeown 57.47

Qualification

The Olympic Qualifying Time for the event was 1:00.25. Up to two swimmers per National Olympic Committee (NOC) could automatically qualify by swimming that time at an approved qualification event. The Olympic Selection Time was 1:02.06. Up to one swimmer per NOC meeting that time was eligible for selection, allocated by world ranking until the maximum quota for all swimming events is reached. NOCs without a female swimmer qualified in any event could also use their universality place.

Competition format

The competition consisted of three rounds: heats, semifinals, and a final. The swimmers with the best 16 times in the heats advanced to the semifinals. The swimmers with the best 8 times in the semifinals advanced to the final.

Schedule All times are Japan Standard Time (UTC+9)

DateTimeRound 25 July 2021 19:00 Heats 26 July 2021 11:53 Semifinals27 July 2021 10:51 Final

Results Heats The swimmers with the top 16 times, regardless of heat, advanced to the semifinals.

Rank Heat Lane Swimmer Nation Time Notes 1 6 4 Kaylee McKeown , 2 5 4 Regan Smith 3 4 4 Kylie Masse 4 6 5 Kathleen Dawson 5 6 3 Emily Seebohm 6 5 5 Rhyan White 7 5 3 Kira Toussaint 8 4 3 Margherita Panziera 9 5 1 Peng Xuwei 10 5 6 Maria Kameneva 11 4 5 Taylor Ruck 12 4 7 Anastasia Gorbenko 13 4 6 Anastasia Fesikova 14 6 2 Cassie Wild 15 5 7 Maaike de Waard 1:00.03 16 4 1 Anna Konishi 1:00.04 17 3 2 Mimosa Jallow 1:00.06 NR 18 5 8 Katalin Burián 1:00.07 6 8 Ingeborg Løyning 1:00.07 20 4 8 Lee Eun-ji 1:00.14 21 5 2 Michelle Coleman 1:00.54 22 6 7 Chen Jie 1:00.63 23 3 5 Béryl Gastaldello 1:00.69 24 6 1 Laura Riedemann 1:00.81 25 3 3 Danielle Hill 1:00.86 26 3 6 Stephanie Au 1:01.07 27 4 2 Simona Kubová 1:01.35 28 2 5 Tatiana Salcuțan 1:01.59 29 3 8 Lena Grabowski 1:01.80 30 3 1 Daryna Zevina 1:01.97 31 2 7 McKenna DeBever 1:02.09 NR 32 3 7 Isabella Arcila 1:02.28 33 2 4 Ali Galyer 1:02.65 34 1 5 Donata Katai 1:02.73 35 2 6 Krystal Lara 1:03.07 36 2 3 Celina Márquez 1:03.75 37 2 1 Danielle Titus 1:04.53 38 2 2 Felicity Passon 1:04.66 39 1 4 Maana Patel 1:05.20 40 2 8 Diana Nazarova 1:06.99 41 1 3 Kimberly Ince 1:10.24 — 3 4 Louise Hansson 6 6 Anastasiya Shkurdai

Semifinals

The swimmers with the best 8 times, regardless of heat, advanced to the final.

Rank Heat Lane Swimmer Nation Time Notes 1 1 4 Regan Smith 57.86 , 2 2 5 Kylie Masse 58.09 3 2 4 Kaylee McKeown 58.11 4 1 3 Rhyan White 58.46 5 1 5 Kathleen Dawson 58.56 6 2 3 Emily Seebohm 58.59 7 2 6 Kira Toussaint 59.09 8 1 7 Anastasia Gorbenko 59.30 , NR 9 2 7 Taylor Ruck 59.45 10 1 2 Maria Kameneva 59.49 11 1 6 Margherita Panziera 59.75 12 2 2 Peng Xuwei 59.98 13 1 8 Anna Konishi 1:00.07 14 1 1 Cassie Wild 1:00.20 2 1 Anastasia Fesikova 1:00.20 16 2 8 Maaike de Waard 1:00.49

Final

Rank Lane Swimmer Nation Time Notes 3 Kaylee McKeown 57.47 5 Kylie Masse 57.72 4 Regan Smith 58.05 4 6 Rhyan White 58.43 5 7 Emily Seebohm 58.45 6 2 Kathleen Dawson 58.70 7 1 Kira Toussaint 59.11 8 8 Anastasia Gorbenko 59.53

References