<p>Eberconazole nanostructured lipid carrier (EBR-NLC) 1% w/w optimization was done using the Quality by Design (QbD) approach, employing a 2³ Full Factorial Design (FFD) for experimental planning, followed by thorough physico-chemical, in-vitro, and ex-vivo evaluations. The 2³ FFD assessed the impact of total lipid amount, surfactant amount, and sonication time on critical quality attributes such as particle size and % entrapment efficiency. <i>In-vitro</i>release testing (IVRT) validation was performed using vertical diffusion cells. IVRT, a compendial technique by pharmacopoeias, was for performing semi-solid formulations analysis. The optimized EBR-NLC 1% w/w was characterized for assay, organic impurities, amplitude sweep, viscosity, IVRT, ex-vivo permeation testing, and skin retention. The validated IVRT technique was meeting the acceptance criteria of regulatory guidelines. The results showed that in-vitro release, ex-vivo permeation, and skin retention were significantly higher (<i>P</i> &lt; 0.05) for the optimized EBR-NLC 1% w/w formulation compared to the innovator formulation (EBERNET^® Cream 1% w/w). Applying QbD principles systematically facilitated the successful development and optimization of an EBR-NLC 1% w/w. The optimized EBR-NLC 1% w/w formulation proved to be a viable alternative, showing stability for at least six months under conditions of 40°C/75% RH and 30°C/75% RH.</p> Graphical Abstract <p></p>