High-rise institutional buildings in India are increasingly essential to accommodate rapid urbanization and growing infrastructural demands. However, their design and construction must be strategically planned to address the unique climatic and environmental challenges of the country. This research examines the critical role of shape geometry and solar radiation in the pre-design phase of these buildings, with a focus on advancing resilient architecture. By optimizing building orientation, shape, and massing, solar heat gain at specific sites in Indian cities can be minimized. To accommodate complex structural systems, basic geometric shapes, often with large glass facades and a central core can be used to balance shape efficiency and space efficiency in the early design phase. This study will analyse six geometric shapes of equal floor area, comparing them based on leasing span, exposed surface area, and solar radiation exposure. The analysis will be conducted for small, medium, and large floor areas, identified through a study of various tall buildings. Space efficiency will be assessed considering conventional corridor connections and standard widths. The impact of building height and site location on shadow casting and solar exposure will also be examined. The goal is to determine the most suitable shape and height for a building in specific geographic locations in India, considering factors like daylighting, site dimensions, energy efficiency, material selection and smart-building systems. This approach will help architects in making informed design decisions that balance space efficiency and energy performance, ultimately leading to sustainable and resilient high-rise institutional buildings.