Climate extremes across the world are growing and posing risks to the coastal regions as it is vital economic hubs, serving as gateways to trade and settlement. Denmark, a country with little elevation and its capital Copenhagen facing risks from sea level rise and flooding with the government’s commitment to tackling them. One of the factors which adds to this absence of progress is that the sea level rise is exceeding the infrastructure capability planning ahead for climate adaptation with projections of changing coastal landscape. Without a framework that could assess and respond to risk factors of the existing coastal development and limits the climate adaptation implementation, contributing to the retreat of communities and damage to economic vulnerability. The research undertaken within the study includes case studies of Lynetteholm, an artificial island and seaward development extension and Holmene, nine artificial islands and seaward development extension. Both case studies are located on the coast of Copenhagen, Denmark. Their strategic objectives are to be new frontiers that are facing climate extremes and facilitating development. This study by focusing on planning practice offers modern and innovative practical implications to mitigate the risks while open for emerging opportunities and a brand-new theoretical framework, the 'Indicators for Decision-Making for Planning Adaptation for Coastal Extension'. Conceptual justification for this approach is Denmark’s planning system and document analysis of Lynetteholm and Holmene planning process with other risk factor models, while practical implications for the 'Indicators for Decision-Making for Planning Adaptation for Coastal Extension' in action are assessed through urgency of the city expansion according to the risks and opportunity provided long term vision and monitoring process of adjustment to the framework.