NCATS Predictor is a website for scientific community to obtain QSAR data sets and models related to the NCATS projects. NCATS Predictor allows the simultaneous prediction of different biological activities and physico-chemical properties of compounds. The service allows to input the different types of structure identifiers: Smiles, SDF files, Images of chemical structures. As output, the service provides predictions from the models calculated for each submitted compound. In addition, the service estimates and reports the applicability domain of each QSAR model. This calculation is performed for each compound with the result that each prediction is annotated with either "In AD" or "Out of AD", indicating whether one can be confident in the prediction or not. This service can be used by researchers for virtual screening of drug-like compounds with desirable biological profile as well as for structure optimization of the compound of interest.