<p>Yttria-stabilized zirconia is widely used as a bioinert ceramic in dental, orthopaedic, and implantable microsystems due to its excellent biocompatibility and mechanical strength. However, its high hardness and brittle fracture–dominated removal behavior make micromachining challenging. This study proposes a hybrid ECDM process with dual mode assistance of magnetic-field and grinding action. Initially, a pilot investigation was conducted to compare conventional ECDM with individual- and dual-assisted configurations. Subsequently, a systematic experimental study was carried out by varying applied voltage, pulse-on time, and tool rotational speed. Hole entrance diameter (HED) and depth of penetration (DOP) were selected as performance responses. Regression models were developed and ANOVA was performed to determine parameter significance. Metaheuristic-driven optimization identified optimal machining conditions. Furthermore, the material removal mechanism was proposed and supported through analytical modeling and material characterization, demonstrating improved machining stability and dimensional accuracy in YSZ micromachining.</p> Graphical abstract <p></p>