Urban planning is fundamentally changing as cities worldwide face increasing climate risks, rapid urbanization, and the demand for sustainable development. Incorporating advanced computation tools, like quantum computing or artificial intelligence, invites a glimpse of planning simulations against complex climate scenarios, efficient resource allocation, and resilient infrastructure development. These include mitigation through energy-efficient development, low-carbon transport, and integrating renewable energies and adaptation, such as resilient coastlines, green–blue infrastructure, and climate-resilient design. Effective climate action in urban areas is required, supported by cross-sectoral planning, participatory approaches, and strong governance to ensure that interventions are context-specific and socially inclusive. Case studies from around the world demonstrate that when climate sensitivity is embedded in policy, spatial planning, and community engagement, vulnerability can be significantly reduced and cities can enhance adaptive capacity. As urban systems become more interconnected, it will be essential for quantum and AI-driven solutions to be leveraged for achieving low-carbon, resilient, and inclusive urban futures.