Swimming at the Tokyo Games will comprise 37 medal events (35 pool events and two 10k open water races). The programs for men and women are identical, with both genders swimming the following strokes/distances:
| Freestyle | Backstroke | Breaststroke | Butterfly | Individual Medley (IM) | Relay | Open Water |
| 50m | ||||||
| 100m | 100m | 100m | 100m | 4x100m freestyle | ||
| 200m | 200m | 200m | 200m | 200m | 4x200m freestyle | |
| 400m | 400m | 4x100m medley | ||||
| 800m | mixed 4x100m medley | |||||
| 1500m | 10,000m |
New for Tokyo is the mixed 4x100m medley relay. The order of strokes is backstroke, breaststroke, butterfly and freestyle. Teams can choose from either gender for a given stroke, but must have two male and two female swimmers.
Races of 200m and Shorter
PRELIMINARY HEATS
The 16 fastest swimmers advance to the semifinals. If there is a tie for 16th, there will be a swim-off between the tied swimmers.
SEMIFINAL RACES – 2 HEATS
The eight fastest advance to the final, which takes place the morning after the heats session. If there is a tie for 8th, there will be a swim-off for the final spot in final. Heat order: fastest time in 2nd heat, 2nd-fastest time in 1st heat, 3rd-fastest time in 2nd heat, 4th-fastest time in 1st heat, etc.
FINAL – 1 HEAT
Occurs the day after semifinals. Ties are not broken; medals are determined based on time in final only (to hundredths of a second).
Races of 400m and Longer, Plus Relays
PRELIMINARY HEATS
The eight fastest swimmers (or teams) advance to the final. If there is a tie for 8th, there will be a swim-off for the final spot in final.
FINAL – 1 HEAT
Occurs one or two days after preliminary heats. Relays can have different swimmers in heats and final.
Ties are not broken, medals are determined based on time in final only (to hundredths of a second).
Open Water
10k race – mass start format… 25 athletes per gender (max two per country). Race video will determine finish order if necessary; if an order can’t be determined from video, the tied competitors will share the same rank. Time varies by course and conditions, but generally it is about a two-hour race.
More information: