Below is the world record progression for the 4×100 metres freestyle relay swimming event. Long course (50 metres) swimming records were recognised by the International Swimming Federation (FINA) in 1908. In the short course (25 metres) swimming events the world's governing body recognizes world records since March 3, 1991.
The women's event was first contested at 1912 Olympics, but the men's didn't appear until the 1964 Tokyo Games. Prior to this the longer 4×200 metres freestyle event was the only male relay event staged.
Records not set in finals: h – heat; sf – semifinal; r – relay 1st leg; rh – relay heat 1st leg; b – B final; † – en route to final mark; tt – time trial
- Men's Event (long course) world progression at www.olympic.org
- Women's Event (long course) world progression at www.olympic.org