Open Topo Data

About Open Topo Data

Open Topo Data is a REST API server for elevation data. It can be self-hosted using Docker with a user's own raster datasets, or accessed through a free public API hosted at api.opentopodata.org that comes pre-configured with several open elevation datasets, including NZ DEM, NED, EU-DEM, Mapzen, ASTER, SRTM, BKG, ETOPO1, GEBCO, and EMOD bathymetry, covering different regions and resolutions. The API has a single point-query endpoint that returns elevation for one or multiple locations, supports Google Polyline format for input, and offers configurable interpolation algorithms; it is largely compatible with the Google Maps Elevation API.

The public API is rate-limited to a maximum of 100 locations per request, 1 call per second, and 1000 calls per day. Self-hosting supports a wide range of raster file formats and tiling schemes, with configuration options for adding datasets and running on Windows and M1 Macs.

The product is aimed at developers who need elevation data for geographic coordinates, either through self-hosted infrastructure or a free hosted service. For higher-resolution needs, the same maintainer offers a paid sister project, GPXZ, which provides managed hosting with global 1m lidar data, a drop-in replacement for the Google Maps Elevation API, priority support, no hard usage limits, EU-only server options, and CORS support for frontend use.

Key features

• REST API for elevation data at single points or batches of points
• Self-hostable via Docker with your own raster datasets
• Supports a wide range of raster file formats and tiling schemes
• Configurable interpolation algorithm and Google Polyline location input
• API compatible with the Google Maps Elevation API
• Free public API preconfigured with multiple open elevation datasets

Frequently asked questions