GTOPO30 is a global digital elevation model (DEM) with a horizontal grid spacing of 30 arc seconds (approximately 1 kilometre). GTOPO30 was derived from several raster and vector sources of topographic information.

GTOPO30, completed in late 1996, was developed over a three year period through a collaborative effort led by staff at the U.S. Geological Survey's Center for Earth Resources Observation and Science (EROS).

The following organizations participated by contributing funding or source data:

• the National Aeronautics and Space Administration (NASA),
• the United Nations Environment Programme/Global Resource Information Database (UNEP/GRID),
• the U.S. Agency for International Development (USAID),
• the Instituto Nacional de Estadistica Geografica e Informatica (INEGI) of Mexico,
• the Geographical Survey Institute (GSI) of Japan, Manaaki Whenua Landcare Research of New Zealand, and the Scientific Committee on Antarctic Research (SCAR).