Nanoparticles of Ni0.5Zn0.5Fe2O4 were prepared using the sol-gel auto-combustion process. The physical properties of as-synthesized NiZn ferrite nanoparticles were examined as a function of annealing temperature (500, 750, and 1000 degrees C), solution pH (5, 7, and 9), and annealing duration (2, 4, and 6 h). The average crystallite size of the powder is evaluated by XRD, confirming the nanoscale dimension of the nanoparticles within the range of 16-41 nm. The annealing temperatures, annealing times, and pH values have a substantial effect on the samples' characteristics. Increasing annealing temperatures caused the crystallite size, particle size, saturation magnetization, dielectric constant, and dielectric loss tangent to increase, but the specific surface area, residual magnetism, coercivity, and band gap energy decreased. In addition, frequency-dependent dielectric characteristics were studied. The crystal structure parameters, particle size, band gap values, and magnetic and dielectric parameters were all affected by the solution pH and annealing time.