adresse.data.gouv.fr vs Ducks Unlimited

The Base Adresse Nationale's API Adresse geocodes and reverse-geocodes French addresses for free with no API key, backed by Etalab and IGN's data.geopf.fr infrastructure (the old api-adresse.data.gouv.fr host now 301-redirects there). Requests and responses use the GeoJSON FeatureCollection format, with each result scored for match confidence and enriched with INSEE city codes, postcodes, and population. A live Origin-header probe confirms open CORS (Access-Control-Allow-Origin: *), so it works directly from browser JavaScript with no proxy.

Ducks Unlimited publishes a public ArcGIS Feature Service listing its university and collegiate conservation chapters as geocoded point locations across the US and Canada. It's read-only and needs no API key — queryable with the standard Esri REST query syntax (WHERE clauses, field selection, spatial filters) and exportable as JSON, GeoJSON, CSV, KML, and several other GIS formats. The dataset is licensed under Creative Commons Attribution-NonCommercial 4.0, so results can be reused non-commercially with attribution.