Establishing and adopting a quick, easy, and cheap method for determining antibiotic Cefadroxil monohydrate (CFL) in its pure form and pharmaceutical preparations. The method involves adopting spectrophotometry in the visible region. The method adopted the oxidation of the studied medicine by an excess amount of N-Bromo succinamide (NBS), then estimated the NBS Excess by bleaching the dye color of Methylene Blue. The maximum wavelength was measured at λ 586 nm. This approach obeys the Beer-Lambert law for the range (5-20 µg. ml^-1), with a correlation coefficient of 0.9980. The calculated molar absorptivity was 1.41× 10³ (L. mol^-1. cm^-1), and Sandall's sensitivity was 0.27 µg. cm^-2. The limit of detection (LOD) was 3.508 µg. ml^-1, as well as the limit of quantification (LOQ), was 11.693 µg. ml^-1. The precision and accuracy of the method are established and checked.
            This study measured the optimal reaction conditions and other analytical variables. It showed decent repeatability, and the relative standard deviation (RSD percentage) was less than 1%.
           The proposed methodology identified the effective implementation of an easy, resilient as well as precise spectrophotometric method to determine Cefadroxil employing N-Bromo succinimide as Cefadroxil oxidant factor and also the unreacted N-Bromo succinimide bleached the methylene blue dye. The process has been successfully extended in different pharmaceutical formulations to evaluate the Cefadroxil drug.