Composite manufacturing is currently one of the most challenging processes for industrial lightweight applications. To date, the process conditions for polymer-based composite manufacturing are evaluated by laboratory measurements: usually, the flow behavior and the curing of the polymer matrix material are characterized by rheology and quality assurance is performed by thermo-physical analysis in postprocess measurements. In contrast a dielectric in-mold sensor offers the possibility to measure the real-time behavior of the polymer during processing. This study focuses on the correlation of simultaneous rheological and dielectric measurements on Hexcel RTM6 using a coupled setup of both techniques. For dielectric measurements a reusable in-mold sensor was used and a calibration, taking into account the cable response, was performed. The results show good agreement with respect to glass-transition temperature and the gel-point. This can be understood by the fluctuation-dissipation theorem that explicitly relates molecular dynamics to the macromolecular mechanical properties under dynamic time-dependent load. Furthermore, it was found that the dynamic viscosity can directly be related to the electrical conductivity. This proves the high potential of dielectric analysis as online-capable technique for material characterization during composite manufacturing. (C) 2018 Wiley Periodicals, Inc.