We present a framework to evaluate the benefits and costs of coastal adaptation through dikes to reduce future flood risk. If no adaptation takes place, we find that global coastal flood risk increases 150-fold by 2080, with sea-level rise contributing the most. Moreover, 15 countries account for 90 % of this increase; that adaptation shows high potential to cost-effectively reduce flood risk. The results will be integrated into the Aqueduct Global Flood Analyzer web tool.