Coastal regions are rich in natural resources due to their unique hydrogeological and ecological characteristics. Changes in these regions, induced by shoreline shifts have been a major concern for coastal communities around the world. With increasing world population, global warming and associated climate change impacts influencing the global environment, the world’s coastlines are under threat. Thus, their mapping and change determination are necessary for sustainable management and conservation measures. This study on the coastline of Kerala attempts to study its change over a 20-year time span, using remote sensing and GIS techniques. The delineation and extraction of shoreline have been performed in two ways—using the AI-based Segment Anything Model for Geospatial data (SAMGeo) for land–water segmentation and coastline delineation, and then index-based method for coastline extraction. While SAMGeo works well for coastline delineation in smaller areas, hardware limitations prevented us from testing it in larger areas. Thereafter, using the Digital Shoreline Analysis System (DSAS) tool, shoreline change rate has been estimated. The study reveals that the coastline of Kerala experiences varying rates of erosion and accretion, owing to several natural and anthropogenic factors, emphasising the dynamic nature of coastline. The maximum erosion rates are in the districts of Kasargod and Kollam at around 18m/year, while Kollam had the highest accretion rates at around 14 m/year. Overall, the findings emphasise the need for further investigation in areas of high erosion to come up with effective conservation and management strategies to protect the coastal communities and the ecosystem.