Iron oxides have found a large number of applications in fields ranging from biomedical to space science. Amongst all iron oxides, the most favored is Fe₃O₄ owing to high saturation magnetization, biocompatibility, and cost-effectiveness. The Fe₃O₄ has an inverse spinel structure with colors ranging from dark brown to black. In this research paper, the Fe₃O₄ and Co-doped Fe₃O₄ nanoparticles were synthesized by co-precipitate method. The X-ray diffractometer (XRD), Scanning electron microscopy (SEM), EDX and RAMAN spectroscopy analysis confirm the formation of synthesized nanoparticles. From UV visible, the optical properties are studied and it is found that after doping of Co, the band gap had increased, and the electrical property of doped Fe₃O₄ goes towards the dielectric behavior. From the vibrating sample magnetometer (VSM), magnetic properties are studied. By Gouy’s balance susceptibility was determined and values calculated, are in good agreement with the susceptibility calculated by VSM. The temperature-dependent conductivity was assessed using the four-probe method. The degradation of dye like methyl orange with the synthesized nanomaterials was studied.