<p>In this study, Mn_0.8Zn_0.2Fe_2-xDy_xO₄ (where x = 0, 0.025, 0.05, 0.075, and 0.1) nanoparticles were synthesized using the sol-gel auto-combustion technique as promising candidates for magnetic hyperthermia. The influence of Dy doping on structural parameters, morphological features, and magnetic properties was investigated. The magnetic nanoparticles (MNPs) were analyzed using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and a vibrating sample magnetometer. X-ray diffraction analysis confirmed the presence of the spinel phase in the MNPs. The results indicated that with increasing Dy³⁺ concentration, the magnetic saturation decreased from 66.24 to 50.84 emu/g, and the crystallite size reduced from 31 to 22 nm. The investigation into magnetic hyperthermia properties revealed that Mn_0.8Zn_0.2Fe₂O₄ and Mn_0.8Zn_0.2Fe_1.95Dy_0.05O₄ nanoparticles demonstrate effective heating capability, achieving specific absorption rate values of 166.5 and 148.3 W/g, respectively, in a water medium at a concentration of 4 mg/ml. The cytotoxicity of the MNPs was evaluated on L929 cell lines using the MTT assay to investigate their viability as heating agents for magnetic hyperthermia. The findings indicate that the produced nanoparticles show considerable potential for use in magnetic hyperthermia applications.</p> Graphical Abstract <p></p>