This paper presents the open-source Python-based parameter extractor (SEKV-E) for the simplified EKV (sEKV) model, which enables the modern low-power circuit designs with the inversion coefficient design methodology. The tool extracts the essential sEKV parameters automatically from the given I-V curves using the direct extraction and the multi-stage optimization process. It also handles the overfitting issue because of non-linear least squares. Moreover, this work demonstrates the SEKV-E as a universal tool by widely applying it to different silicon technologies, temperatures, dimensions, and back-gate voltages.