As of February 2022, how many female athletes have run the 400 metres in under 48 seconds?

The 400 metres, or 400-metre dash, is an endurance sprint race event in track and field competitions. It has been featured in the athletics programme at the Summer Olympics since 1896 for men and since 1964 for women. On a standard outdoor running track, it is one lap around the track.

The only women to have broken the 48-second barrier in the 400 metres are Marita Koch (47.60 seconds, Canberra, Australia, 1985) and Jarmila Kratochvílová (47.99 seconds, Helsinki, Finland, 1983). Kratochvílová was Koch's main rival over the distance and also a 400 metres world record holder in the early 1980s. To this day, no other woman has come within a half a second of Koch.

Marita Koch (born 18 February 1957) is a German former sprint track and field athlete. During her career she collected 16 world records in outdoor sprints as well as 14 world records in indoor events.

Jarmila Kratochvílová (born 26 January 1951) is a Czech former track and field athlete. She won the 400 metres and 800 metres at the 1983 World Championships, setting a world record in the 400 m.