The present study contains the information about the spin polarization, structural, optical and mechanical behavior of KXF3 (X = Ir, Rh) compounds, which were ascertained using method of FP-LAPW; employed within WIEN2K code. Optimized lattice constants were found as: 4.323 Å & 4.25 Å for the KIrF3 and KRhF3, respectively. The structures of both the studied materials were found stable in the cubic phase. Spin-polarized results of the electronic properties demonstrated the dual nature of metallicity of the presently studied compounds. In semiconducting case the gap between the energy bands were calculated and recovered as 1.8 eV for KIrF3, while 2 eV for KRhF3. The study of the density of states also confirms the band structure results of both the investigated compounds. From the partial density of states for the spin-up orientations; it became evident that Ir and Rh are mainly responsible for the conducting behavior of the investigated materials. From the investigation of optical study of both the compounds revealed their good optical response over the wide range of energy spectrum. Elastic properties were calculated through IR-Elastic package. The obtained elastic parameters confirmed the mechanical stability, ductile nature, and anisotropic behavior of the studied materials.