Assessing shoreline change is essential for identifying coastal accretion and erosion and understanding coastal morphology and dynamics. Coastal erosion represents a significant hazard to coastal communities, particularly in areas increasingly prone to coastal disasters. This study investigates shoreline changes along the Point Calimere coast in Nagapattinam district, Tamil Nadu, focusing on decadal changes from 2000 to 2024. The Digital Shoreline Analysis System (DSAS) was utilized to assess these changes using satellite imagery from Landsat 7—Enhanced Thematic Mapper Plus (ETM+) and Landsat 9—Operational Land Imager (OLI), both with a spatial resolution of 30 m, acquired during the pre-monsoon periods of 2000 and 2024. DSAS effectively analyzes shoreline changes through key metrics, including Net Shoreline Movement (NSM), End Point Rate (EPR), and Shoreline Change Envelope (SCE). The long-term shoreline dynamics (2000–2024) at 100 m transects along the coastal stretches showed the remarkable changes due to erosion and accretion processes, and the EPR is measured at the average erosion rate of −0.20 m/yr (found in 48.22% of transects), and an average accretion rate of 0.25 m/yr (31.18% of transects), respectively, with the uncertainty value of +/− 1m. The maximum erosion rate is −18.80 m/yr at the transect ID 943, in segment 3 (Point Calimere – Kodiyakarai), meanwhile the maximum accretion rate is at 17.29 m/yr at the transect ID 1771, in segment 5 (Manamelkudi). Notably, the 20.60% of transects in moderate change (seasonal erosion/accretion) with an average rate of 0.12 m/yr, and indicates a predominant trend of coastal erosion along the Point Calimere stretch. These metrics provide crucial insights into coastal erosion and accretion dynamics, which are essential for effective coastal zone management and planning. The findings from DSAS offer valuable data for the development of strategies aimed at mitigating coastal erosion and promoting sustainable coastal development.