An extensive study on morphological parameters of ceramic sponge structures of different material, porosity, and pores per linear inch (ppi) number was performed. Volume image analyses of magnetic resonance imaging (MRI) and X-ray tomography (CT) measurements were carried out to determine experimentally the geometric specific surface area of the structures. Furthermore, face and strut diameters, porosities, and densities were assessed through conventional methods including optical microscopy, mercury porosimetry, and helium pycnometry. The resulting data were used to evaluate morphological models representing the irregular strut network by packings of regular polyhedra. On the basis of an adapted Weaire-Phelan model, a novel correlation was developed that enables the calculation of the specific surface area of sponges with high accuracy. The input parameters for this correlation are easily accessible by standard microscopy and porosimetry measurements.