Neurons rely on the interplay between dendritic morphology and ion channels to transform synaptic inputs into a sequence of somatic spikes. Detailed biophysical models with active dendrites have been instrumental for exploring this interaction. However, such models can be challenging to understand and validate due to the large number of parameters involved. In this work, we introduce DendroTweaks — a framework designed to illuminate how morpho-electric properties map to dendritic events, and how these dendritic events shape neuronal output. Through its graphical interface, users can access the morphological and biophysical parameters of a single-cell neuronal model and adjust them with real-time visual feedback. In particular, DendroTweaks features interactive fine-tuning of ion channel kinetics and distributions, as well as the dynamics and allocation of synaptic inputs. It offers a comprehensive approach for automatic standardization and refinement of voltage-gated ion channel models, making them more transparent and reusable. It supports running various experimental scenarios while recording from multiple dendritic and somatic locations. Finally, it aims to enhance our understanding of which dendritic properties are essential for neuronal input-output transformation. With this knowledge, one can simplify models through a built-in morphology reduction algorithm and export them for further use in faster, more interpretable networks. DendroTweaks will enable researchers to gain a deeper understanding of the model's behavior, particularly by making dendritic input-output transformation easier to comprehend and design on demand. This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 860949.