The OpenCage Geocoder is built from great open source products and uses equally great open data to make it all work. This is what's under the API. Most of the products and data we use have a follow up link to each product's additional data sources. It's a worthwhile exercise to click through to see just how much open geo-data there is in the world.
Nominatim and OpenStreetMap
Please note the OpenStreetMap Foundation's guidelines around geocoding, specifically the view that geocoding does not trigger the share-alike obligations of the ODbL.
The what3words Server Software converts searches that are compatible with what3words into geographic co-ordinates, and converts geographic co-ordinates into what3words.
A C library for parsing/normalizing street addresses around the world.
©PSMA Australia Limited licensed by the Commonwealth of Australia under the Open Geo-coded National Address File (G-NAF) End User Licence Agreement.
Data under CC BY 4.0, with the additional restriction that the open G-NAF data must not be used for the generation of an address or the compilation of an address for the sending of mail unless the user has verified that each address to be used for the sending of mail is capable of receiving mail by reference to a secondary source of information.
Mapzen Terrain Tiles
- ArcticDEM terrain data DEM(s) were created from DigitalGlobe, Inc., imagery and funded under National Science Foundation awards 1043681, 1559691, and 1542736;
- Australia terrain data © Commonwealth of Australia (Geoscience Australia) 2017;
- Austria terrain data © offene Daten Österreichs – Digitales Geländemodell (DGM) Österreich;
- Canada terrain data contains information licensed under the Open Government Licence – Canada;
- Europe terrain data produced using Copernicus data and information funded by the European Union - EU-DEM layers;
- Global ETOPO1 terrain data U.S. National Oceanic and Atmospheric Administration
- Mexico terrain data source: INEGI, Continental relief, 2016;
- New Zealand terrain data Copyright 2011 Crown copyright (c) Land Information New Zealand and the New Zealand Government (All rights reserved);
- Norway terrain data © Kartverket;
- United Kingdom terrain data © Environment Agency copyright and/or database right 2015. All rights reserved;
- United States 3DEP (formerly NED) and global GMTED2010 and SRTM terrain data courtesy of the U.S. Geological Survey.
Under The API
What makes the OpenCage geocoder run? We're glad you asked ...
The OpenCage geocoder is an aggregating API. Every query you shoot at the API generates calls to the various back-end geocoders we have installed.
The bulk of the geocoder code is written in Perl, apart from the back-end geocoders which are written in a whole plethora of languages. You can read more about how we use Perl in this interview we did with Built in Perl in Nov. 2017.
We rely on many different tools and services to operate our business. We regularly feature them in an ongoing "Tools we use" series on our blog.
Please take a peak at the various software projects we've opensourced .
The API is served by Apache and the whole lot runs on top of servers running ubuntu, a version of Linux.
Twitter and geolocation icon made by Anton Saputro, CC 3.0 BY
For preselecting currency and country on our payment pages we use MaxMind GeoLite2 database, CC BY-SA 4.0