An Olympic-size swimming pool is the type of swimming pool used in the Olympic Games, where the race course is 50 metres (164.0 ft) in length. This is typically referred to as "long course", distinguishing it from "short course" which applies to competitions in pools that are 25 metres (82.0 ft) in length. If touch panels are used in competition, then the distance between touch panels should be either 25 or 50 metres to qualify for FINA recognition. This means that Olympic pools are generally oversized, to accommodate touch panels used in competition.

An Olympic-size swimming pool is used as a colloquial unit of volume, to make approximate comparisons to similarly sized objects or volumes. It is not a specific definition, as there is no official limit on the depth of an Olympic pool. The value has an order of magnitude of 1 megaliter (ML).

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