As was mentioned by others, legal, but not very common. At least not anymore. Being that my wife and I only go every few years I get more of a snapshot in time rather than a continuous movie. 14 years ago there was a much higher percentage who would go topless than I saw on more recent visits. Interesting, although there are more American's than French on the beaches most days, this trend mirrors what has happened in France itself where topless sunbathing has become less common in recent years.