The sound of voice allows people to make judgments about one’s feelings, personality, attitudes towards others, and a multitude of fundamental cues that underpin complex social relationships. In particular, in relation to the perception of sincerity and honesty, there plenty of scientific and anecdotal evidence that it is (at least partially) determined by facial features and expressions as well as gestures and body postures. On the contrary, and despite the fact that the tone of voice is one of the most common cues people use to discern information about other people intentions and feelings, very little is known about the relation between speech prosody and the perception of sincerity. The overarching goal of this ongoing project is to discover which aspects of the tone of voice while speaking can also be an indication of sincerity. For that, various voice recordings of different people apologising to a virtual person were recorded and used to develop computational models that permit estimating the level of sincerity automatically from any given speech recording. In this installation, people can interact with this software and understand how changes on the tone of their voices can convey sincerity to other people.