The demand for sustainable construction materials has intensified the search for eco-friendly alternatives in brick manufacturing. This research integrates a multi-criteria decision-making (MCDM) framework with Taguchi design to evaluate and optimize sustainable brick compositions. By applying CRITIC–CODAS, objective weights of sustainability criteria were derived and used to compute a Sustainability Index, which served as the response variable in a Taguchi L27 experimental design. Results highlight carbon black as the dominant factor, contributing over 52% of sustainability variation, while PCE and gypsum also showed meaningful influence. In contrast, cement and quarry dust exhibited negligible effects. This novel integration of CRITIC–CODAS with Taguchi demonstrates a systematic method to rank, optimize, and validate brick compositions for eco-friendly construction. Practical recommendations are provided for manufacturers and policymakers to prioritize innovative additives over conventional binders to achieve greener outcomes.