Nanostructured CdFe₂O₄ has emerged as a promising electrode material for supercapacitor applications because of its multiple oxidation states, excellent electrochemical activity, and structural stability. In the present work, CdFe₂O₄ nanoparticles were successfully synthesized using a simple and cost- effective sol–gel auto-combustion method. The synthesized sample was characterized using various analytical techniques to investigate its structural, morphological, and electrochemical properties. X-ray diffraction (XRD) analysis confirmed the formation of a well-crystalline cubic spinel CdFe₂O₄ phase without noticeable impurity peaks, and the average crystallite size was found to be approximately 41 nm. Fourier transform infrared (FTIR) spectroscopy revealed characteristic metal–oxygen stretching vibrations corresponding to the ferrite structure. Scanning electron microscopy (SEM) images showed porous agglomerated nanoparticles with irregularly distributed interconnected grains, providing a large active surface area favorable for electrochemical reactions and ion diffusion.The electrochemical performance of the CdFe₂O₄ electrode was investigated using cyclic voltammetry (CV), galvanostatic charge–discharge (GCD), and electrochemical impedance spectroscopy (EIS). The CV curves exhibited distinct anodic and cathodic redox peaks, confirming pseudocapacitive charge storage behavior. The GCD profiles demonstrated nearly symmetric charge–discharge characteristics with good electrochemical reversibility and capacitance retention. EIS analysis indicated low internal resistance and efficient charge-transfer kinetics, suggesting enhanced ion transport during electrochemical cycling. The overall results demonstrate that the synthesized CdFe₂O₄ nanoparticles possess favorable structural and electrochemical properties, making them suitable candidates for advanced high-performance supercapacitor electrode applications.