This web application provides free and open access for the broader research community to the experimental planning utilities that are incorporated into ThermoData Engine (TDE) [J. Chem. Inf. Model. 2005, 45, 816-838]. TDE provides recommendations for the relative merit of a proposed measurement via assessment of the existing body of knowledge, including availability of experimental thermophysical property data, variable ranges studied, associated uncertainties, state of prediction methods, and parameters for deployment of prediction methods. The web applications provides utilities for the assessment of specific property measurements for pure and binary chemical systems, the broader data needs of pure systems, and recommendations for binary mixture measurements that could extend the current UNIFAC model. The primary focus of this recommendation service is molecular organic compounds. Some common inorganic and organometallic compounds are included, but, in general, polymers, radicals, ions, salt and acid solutions, metals, metal oxides, and inter-metallics are not considered. References NIST Standard Reference Data 103a and 103b.