Many works has been made to improve the users browsing on Web sites notably with the adaptation techniques which allow to guide the users according to their profile in order to direct them to the most interesting pages. Considerable improvements has been made in this domain but it is very difficult to judge the impact of the implementation of such techniques on a site. In this paper, we are going to present a prototype which we set up to study the architecture of a Web site with regard to its semantics. The aim is to try to judge the Web site modelling quality by studying the users browsing with regard to various presented concepts. It allows to have an effective tool to advance the defects of certain Web sites in the optics to improve presentation to the users.