Pred-Skin is a fast and reliable web app to assess chemically-induced skin sensitization. The Pred-Skin app is based on statistically significant and externally predictive QSAR models of skin sensitization. The models were built using the largest database containing human and LLNA data. Probability maps allow the visualization of predicted fragment contribution. This method provides an easy interpretation of the predicted activity, allowing the user to easily propose structural modifications. It is one of the only tools available for predicting skin sensitization based on human data.