Bulk specimens of Cobalt-doped Zinc Oxide (CZO) thin films were fabricated using the Sol-Gel dip coating technique, with diverging Cobalt (Co) proportions. It was found that Co was successfully incorporated into the of ZnO’s crystal lattice, and diffraction pattern analysis affirmed the presence of a hexagonal wurtzite crystalline arrangement. The obtained particle size were varied between 21.871 and 31.626 nm. Optical properties of CZO thin films were investigated through absorption curve, showing a noticeable reduction in the forbidden energy gap with increased doping proportion and annealing temperature. The forbidden energy gap ranged from 3.20 eV to 3.31 eV, with the minimum electronic band gap (3.20 eV) observed for a thin film of CZO doped with 1 at. %, treated at 450 °C. The pure ZnO thin film displayed typical diamagnetic behaviour and as the Co doping increases the material approaches ferromagnetism. These findings indicate that CZO thin films are ideal for transparent conducting oxides (TCOs) for solar cells, while their ferromagnetic properties make them promising for sensor applications.