200m Individual Medley 200m Breaststroke Leon Marchand Katie Ledecky Women's 200m Breaststroke American Records Gretchen Walsh Event Records Individual Medley 800m Freestyle Individual Performances Léon Marchand Siobhan Haughey Pan Zhanle Men's Swimming Records Historical Performances 1500-meter Freestyle Individual Achievements Ami Dadaon Short-Course Records 100m Backstroke 400m French Records Historic Performances 100-meter Backstroke Short Course 200m 4 nages Performance Metrics Backstroke Men's 200-Meter Short Course Medley Men's 100m IM Freestyle Racing Emma McKeon Short Course World Championships 200m Medley Record 200m 4 Nages 200 m Medley Event Highlights 1500 Meter Freestyle Short-Course Freestyle Women's Events 100 Metres Freestyle 200 Individual Medley Record 50m Freestyle Olympic Records Michael Phelps Athletes Women's 100-metre Butterfly 100m Butterfly Record Women's 100-Meter Backstroke