Characterizing the morphometric parameters of noble metal nanoparticles for sensing and catalysis is a persistent challenge due to their small size and complex shape. Herein, we present an approach to determine the volume, surface area, and curvature of non-symmetric anisotropic nanoparticles using electron tomography and design-based stereology without the use of segmentation tools or modeling of the particles. Finally, we apply these tools to aggregates to estimate their fractal dimension.