A lap is defined as one length of the pool… from one side to the other.

A mile swim is **30 laps in an Olympic-size** swimming pool. Each lap is 50 meters, so the total distance is 1,500 meters in a mile swim. This is shy of a true mile which is 1,609.344 meters. Similarly, a mile is **60 laps in a short course meters** swimming pool.

On the other hand, a mile swim is **66 laps in a short course yards** swimming pool. Each lap is 25 yards, so the total distance is 1,650 yards in a mile swim. This is again is shy of a true mile which is 1,760 yards.