A precise, specific, and sustainable ultraviolet (UV) spectrometer technique was established and validated for measuring and determining dapagliflozin and sitagliptin in combined therapeutic dosage forms. The simultaneous equations approach to spectrophotometric assessment employed methanol as a solvent. Dapagliflozin and sitagliptin were identified to have λmax values of 224 nm and 263 nm, consequently, according to the previously mentioned approach. The concentration ranges employed to assess linearity for dapagliflozin, and sitagliptin were 1–13 µg/mL, and 5–35 µg/mL, correspondingly, The r2 values of dapagliflozin (r2 = 0.999) and sitagliptin (r2 = 0.9998) were found. ICH specifications statistically validated the developed approach's correctness, precision, and other statistical studies. Consequently, this method can be used to regularly analyze the combination dosage forms of sitagliptin and dapagliflozin.