This paper proposes an improved analytical stray capacitance model for inductors. It considers the capacitances between the winding and the central limb, side limb, and yoke of the core. The latter two account for a significant proportion of the total capacitance with the increase of the core window utilization factor. The potential of the floating core/shield is derived analytically, which enables the model to apply not only for the grounded core/shield, but also for the floating core/shield cases. Based on the improved model, an analytical optimization method for the stray capacitance in inductors is proposed. Moreover, a global Pareto optimization is carried out to identify the trade-offs between the stray capacitance and ac resistance in the winding design. Finally, the analysis and design are verified by finite element method (FEM) simulations and experimental results on a 100 kHz dual active bridge (DAB) converter.