Allows forecast of Cytochrome P450 enzymes (P450s) sites of metabolisms (SOMs). XenoSite is a machine-learning approach to model P450 metabolism using a neural network. It can identify experimentally observed SOMs within the top two rank positions for substrate sets of each P450 isozyme. It also can compute SMARTCyp predictions for P450 metabolism. These predictions are available for downloading in a flat file.