The objective of this study was to evaluate the conditions that favor the stability of magnetite nanoparticles synthesized by coprecipitation of iron salts. This was done with the aim of maximizing their effectiveness in various applications and ensuring homogeneous dispersion over time. The impact of various factors, including sonication power and time, use of pH modifiers, and surface preparation, on the time-dependent evolution of the transmittance of the prepared nanofluids was investigated through the analysis of vectorial distances between the generated 350 and 650 nm spectra for each time analyzed. The nanofluids were prepared by dispersing the nanoparticles in deionized water using an ultrasonic homogenizer, in accordance with a factorial experimental design that generated 32 runs. The stability of the samples was evaluated through direct observation, visible spectroscopy, and zeta potential measurement. The findings suggest that the combination of unwashed nanoparticles, pH mo