In Europe, the answer is unequivocally 50 meters. However, in the United States the term "Olympic size pool" usually refers to a pool that is half that size, or 25 meters.
An olympic swimming pool is 2m deep, 50m long and 25m wide.
In the London 2012 Olympic Games the pool is 50 m length.
164.041995 feet
A semi-olympic pool is 25 meters long by 12.5 meters wide with a depth of between 1.2 and 1.6 meters.
The pool is standard Olympic size: 50 meters The pool is standard Olympic size: 50 meters
50 m
50 meters .
50 meters
I am assuming by professional, you mean Olympic size. An Olympic size pool is 50 meters. The most common lap pool is 25 yards.
Olympic Sized/Long Course -- 50m Shortcourse -- 25m
It is 100 yards long An Olympic sized swimming pool is 50 meters long by 25 meters wide (164 feet x 82 feet).
It is 3 metres deep and 50m long