Abstract The significance of river morphology and the need to develop reliable morphological prediction methods require better knowledge of river-bed and island topography. This study focuses on techniques for determining the topography of exposed chars (char is defined here as a vegetated island (island-char) or an area of vegetated land within the braid belt that is attached to the floodplain (attached-char)) within the braid belt of the Brahmaputra-Jamuna River, based on land cover and age of the land surface. Traditionally, char topography is assessed from widespread field surveys, which are both costly and time-consuming. In addition, the river is highly dynamic and the utility of field survey is limited beyond 1 year. This study explores the use of remote sensing as a cost-effective and rapid method of acquiring synoptic data on land elevations in the low relief of the Brahmaputra-Jamuna braid belt. The land elevations assessed indirectly by remote sensing are combined with ground surveys for calibration. The results indicate that the rate of char elevation growth is initially high, but decreases as the char matures. It appears that growth ceases after about 7 years, and that char elevation reaches a level that is maintained, provided the char is not subjected to erosion. A multitemporal satellite image database and field survey measurements at corresponding dates are required to develop the method. Extensive survey data are not available, hence verification of the method is limited. Despite this limitation the results give approximate char heights, which can be used for sediment budgeting and other morphological studies.