GeoJS vs Nominatim

GeoJS is a free, no-signup IP geolocation lookup that returns country, city, ASN, and timezone data as JSON or JSONP over HTTPS with open CORS. It's built for simple client-side and ChatOps integrations rather than high-volume commercial traffic, and has no paid tier.

Nominatim provides worldwide forward and reverse geocoding built entirely on OpenStreetMap data, needing no API key — only a descriptive User-Agent or Referer header identifying the calling application. The public instance at nominatim.openstreetmap.org is a free courtesy service, not a commercial product: its usage policy caps requests at 1 per second, forbids autocomplete-style querying and bulk/parallel scripts, and requires caching results rather than re-fetching them. Heavier users are expected to self-host Nominatim against their own OSM extract instead of relying on the shared instance.