With increasing calls of electrification for trans-portation (e.g, electric vehicles, hybrid or electric aircraft), the need for systematic guidelines that gauge passive component specific energy density for weight-optimized converter design has be-come apparent. Observing a lack of data sets and corresponding modeling process for passive components that usually dominate a converter's weight, this work proposes a transformation that estimates the specific energy density of passive components from comprehensively surveyed volumetric energy density data and empirical specific density models, and thus forms a convenient guideline for converter weight optimization. The proposed model is then applied to a converter designed for electric aircraft applications to showcase the component mass estimation and selection process along with estimation accuracy.