The objective of this article is to present a study that has been made about the use of the interactive persuasion criteria grid in order to identify persuasiveelements in the interfaces. Two groups have been created, “criteria” and “control”. Both should identify persuasive elements of two interfaces: social network (Facebook) and e-commerce (Cdiscount). During the second phase of the experiment, the “criteria” group had an access to the grid. 27 participants were recruited for this study. The results show that the participants have found more persuasive elements with the grid and that the identification performance was better for the e-commerce website. The average evaluation performance is significantly different (p = 0.000) on the two sites. On Facebook, participants' performance was 9.7% ("control" group) and 23.8% then ("test" group); and for Cdiscount respectively 21.7% ("control" group) and 43.6% ("test" group). The set of guidelines really allows to increase the identification of forms of persuasion in interfaces.