Geocoding — entry 058 of 80
Open Topo Data
Open Topo Data is an open-source, self-hostable REST server for elevation lookups, distributed as a Docker image with support for ASTER, SRTM, EU-DEM, ETOPO1, NED, NZ DEM, and several bathymetry datasets. Its free public API (api.opentopodata.org) needs no key and returns elevation in meters for one or more lat/lng points as plain JSON; a live probe against it confirms no CORS header, matching the existing record. There's no vendor pricing tier for the hosted API itself — paid options only cover optional commercial support for self-hosting.
Open Topo Data is an open-source, self-hostable elevation lookup server. Its free public API needs no key and returns elevation in meters for one or more latitude/longitude points, drawn from datasets such as SRTM, ASTER, and ETOPO1. You can also run your own instance with Docker if the public limits are too tight.
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<a href="https://greatapis.com/api/open-topo-data/"><img src="https://greatapis.com/badge/open-topo-data.svg" alt="Scored 74 on greatapis.com"></a>Auth quickstart
- No API key required. Pick a dataset name as a URL segment (
srtm90min the example below) and pass one or morelocations.
Your key is stored only in this browser (localStorage) and sent directly to the API — never to greatapis.
Get elevation for a coordinate
GEThttps://api.opentopodata.org/v1/srtm90m?locations=57.688709,11.976404
{
"results": [
{
"dataset": "srtm90m",
"elevation": 55.0,
"location": {
"lat": 57.688709,
"lng": 11.976404
}
}
],
"status": "OK"
}Developer reference
1 call/second, 1,000 calls/day (free public instance)
Gotchas & limits
- The docs state the free public API's limits plainly: "Max 100 locations per request. Max 1 call per second. Max 1000 calls per day." Batch several coordinates into one request's
locationslist (separated by|) rather than firing one call per point. - The public API has no CORS header. A live probe confirmed no
access-control-allow-originheader on the response, so browser JavaScript calling it directly across origins will be blocked — route the request through your own backend instead. - For workloads past the free limits, the docs point to a separate paid sister product, GPXZ, rather than a paid tier of Open Topo Data itself. The docs list GPXZ's features as "Managed hosting, load balanced for redundancy", "No hard usage limits", and "CORS (so you can use the API in your frontend webapp)".