NWP SAF users can now experiment with RTTOV simulations and 1D-Var retrievals directly online with the new Web Based Satellite Sounding Training Application https://sounding.trainhub.eumetsat.int/. A selection of satellite instruments and input profiles from the NWP SAF profile database are used for the simulation and the retrieval tools. Users can modify the temperature, humidity, observation and background errors, noise, satellite zenith angle, or surface emissivity, and see how it impacts simulations and retrievals. The tool can display the results of the K-Model (Jacobian) as well as the result of the Direct Model (brightness temperatures and radiances), and the differences between the different runs.