India’s coastline has been officially revised to a length of 11,098.81 km, up from the long-standing 7,516.6 km figure used since the 1970s.
The recalculation, led by the National Hydrographic Organisation and the Survey of India, involved a significant upgrade in measurement scale and methodology. The revised measurement, endorsed in an April 29 circular by the Ministry of Ports, Shipping and Waterways, reflects more accurate data captured at a scale of 1:250,000 compared to the earlier 1:4,500,000 or smaller. Officials noted that larger-scale mapping reveals finer geographical features such as bays, inlets, and minor irregularities, which were previously smoothed over in smaller-scale maps. The update also includes the addition of the coastline of offshore islands, which were previously underrepresented. A total of 1,298 offshore entities—comprising 1,059 islands and 239 islets—have been factored into the new total. The use of the High Water Line around each island added substantial length to the national coastline.
Authorities explained that older calculations likely relied on manual methods and lower-resolution maps, which did not fully account for the intricate coastal contours or the extensive network of offshore landforms. The recalibrated figure was finalised after extensive consultations and agreement from several national bodies, including the Indian Coast Guard, Ministries of Home Affairs, External Affairs, Environment, Forest and Climate Change, Earth Sciences, Jal Shakti, and the National Remote Sensing Centre.
The Coastal Protection and Development Advisory Committee (CPDAC) approved the updated coastline length after all coastal states and Union Territories gave their concurrence. Moving forward, the country’s coastline will be reviewed every 10 years using the latest data and technologies.
