Offshore wind is a potential contributor to India’s renewable energy transition due to its long coastline. While previous studies have primarily focused on wind speed and wind power density (WPD) using ERA5 or CMIP6-based projections, they often overlook turbine-specific characteristics and practical energy generation metrics. In the present study, we estimate India’s offshore wind energy potential by integrating technological evolution and climate change projections. Wind data from ten CMIP6 GCMs are bias-corrected via Weibull-distribution-based quantile mapping, and a multi-model ensemble is developed to generate robust, climate-consistent projections of offshore wind resources. Seasonal and spatial analysis reveal peak resource availability during June–August, with additional gains in September–November and identify southern offshore regions as the most favourable due to consistent and rich wind resources. To estimate practical energy potential, we incorporate turbine-specific performance metrics, including capacity factors (CF) and annual energy yield (AEY), alongside technological constraints and exclusion zones. Results indicate that mid-sized turbines (6–8 MW) exhibit notable efficiency, while ultra-large 15 MW turbines deliver the highest AEY in medium-depth waters, generating up to 10,266 PWh by the late 21st century. Normalized AEY increases of +2.2–2.5 % (mid-future) and +3.4–3.9 % (far-future) demonstrate the combined benefits of technological scaling and climate-driven resource shifts. This work integrates bias-corrected climate projections with turbine-level performance metrics, providing high-resolution, climate-consistent assessments to support offshore wind project development, long-term planning, and policy decisions.