This report presents a novel approach to quantifying and comparing national efforts towards the United Nations Sustainable Development Goals (UNSDGs) by developing a Sustainable Development Index (SDI) using Mixed-Integer Linear Programming (MILP). The methodology uniquely integrates MILP to optimize the weighting of various sustainability indicators, offering a robust and mathematical foundation for the SDI. This approach not only captures the discrete and linear aspects of sustainability indicators but also aligns the resulting index with existing measures such as the Human Development Index (HDI) and Environmental Performance Index (EPI). Through meticulous data collection, normalization, and MILP-based analysis, the report examines 17 unique indicators, each representing a specific UNSDG. The study employs advanced optimization tools, including Gurobi Optimizer and Julia programming language, to compute the SDI, ensuring an objective and reliable comparison of countries’ sustainability performances. The report reveals insightful findings, with the SDI offering a clear and quantifiable measure of progress towards the UNSDGs. The outcome of this research has significant implications for policymakers, researchers, and the public, providing a nuanced understanding of national sustainability efforts. It underscores the utility of MILP in addressing complex global challenges and sets a precedent for future research in sustainable development assessment.