Background: The countries of the Gulf Cooperation Council (GCC) face a significant diabetes burden. Preventing, or at least delaying onset of Type 2 diabetes mellitus (T2DM) requires accurate and timely identification of at-risk individuals with prediabetes. Traditional screening focuses on glucose and HbA1c alone and does not include other readily available data that can better identify risk and guide intervention. Methods: We developed a comprehensive web-based cardiometabolic risk calculator combining the classic homeostasis model assessment (HOMA1), triglyceride-glucose (TyG) index, metabolic syndrome evaluation (ATP III and IDF criteria), diabetes risk prediction adapted from validated models including QDiabetes-2018 and UK Biobank cohort studies, and cardiovascular risk trajectory with Lipoprotein(a) integration. The calculator uses ethnicity-specific thresholds for Middle Eastern, South Asian, and other populations, and provides AI-generated clinical summaries with multi-language patient education materials. Case: An 18-year-old Emirati male with obesity, prediabetes, severe insulin resistance, and compensatory beta-cell hypersecretion had a calculated 10-year diabetes risk exceeding 55%. This quantitative risk estimate motivated intensive lifestyle modification combined with tirzepatide and metformin. After six months, he achieved 17% weight loss, normalization of insulin resistance and beta-cell function, prediabetes resolution and diabetes risk reduction to under 10%. Conclusion: Comprehensive metabolic phenotyping with quantitative risk communication can identify high-risk individuals, characterize their metabolic dysfunction, and motivate behavioral change. This freely available tool addresses the need to identify individuals at high 10-year risk of progression to T2DM and elevated lifetime cardiovascular risk, thereby allowing more timely intervention.