X-ray powder diffraction (XRPD) profiles provide valuable information on the geometrical shape of crystallites. This work delves into the complexity of determining the geometrical shape of crystallites, including plate-like and spherical TiO2 specimens, and discusses crucial parameters of edge length, shape coefficient, and orientation vector. The analysis demonstrates the necessity of using both line-broadening analysis and preferred orientation to elucidate the underlying physics of XRPD analysis. The choice of empirical formula is illustrated in analyzing plate-like crystallites with the characteristic of flat morphology. For spherical crystallites, the March-Dollase formula is recommended. •X-ray diffraction powder profiles are used to determining crystallite morphology.•Crystallite shape with edge length (L), shape coefficient (η), and orientation UVW.•The integration of line-broadening analysis and preferred orientation provides insights into crystallite shape.