Free DEM Data Download & Elevation Models
GEBCO
Quick answer: Use GEBCO for 15 arc-second global ocean bathymetry combining satellite altimetry with ship soundings — the standard reference for seafloor depth worldwide, with a live WMS map preview and public-domain grid downloads.
About this dataset
General Bathymetric Chart of the Oceans (GEBCO) global bathymetric grid at 15 arc-second resolution combining satellite altimetry and ship soundings for seafloor mapping.
GEBCO is a global bathymetric dataset produced under the joint auspices of IHO and IOC (UNESCO). The GEBCO_2026 grid provides 15 arc-second (~450 m) resolution seafloor topography derived from satellite altimetry and shipborne echo soundings, with a companion TID (type identifier) grid. Grids ship as netCDF or GeoTIFF (about 4 GB each, ~7 GB unpacked), a new version lands every July, and the map preview above streams the official GEBCO WMS so nothing large is downloaded to your browser.
What the GEBCO grid ships with
Figures below come from the official GEBCO_2026 release notes; the map preview above needs none of them locally.
15 arc-second global grid
~450 m at the equator
Continuous terrain model for ocean and land, plus a Type Identifier (TID) grid describing which source data each cell rests on.
~4 GB per format
netCDF or GeoTIFF
Global files unpack to roughly 7 GB. Subset downloads avoid the full transfer when you only need a region.
Annual July release
GEBCO_2026 current
Each July a new grid is published; the WMS in the preview is updated to the latest release.
Public domain
Attribution requested
The grid may be used free of charge, commercially included, with the GEBCO Compilation Group citation.
How to download
- 1 Use the live WMS preview above to inspect seafloor relief before downloading anything.
- 2 Open the GEBCO area download app and draw a bounding box if you only need a region.
- 3 Pick netCDF or GeoTIFF and download (the full global grid is roughly 4 GB compressed).
- 4 Load the grid in QGIS, GeoDataViewer Studio, or any NetCDF-compatible tool; land values come from a global DEM blend.
FAQ
How does GEBCO differ from ETOPO1?
GEBCO focuses on ocean bathymetry at 15 arc-second (~450 m) resolution using the latest satellite altimetry and ship soundings, while ETOPO1 is a coarser 1 arc-minute (~1.8 km) product combining older sources. For modern ocean depth work, GEBCO is the higher-quality choice.
Does GEBCO include land elevation?
Yes. GEBCO grids include land elevations derived from a global DEM (currently a blend of SRTM and other sources), but the primary strength is ocean bathymetry. For detailed land terrain, use SRTM or Copernicus DEM instead.