Callook.info vs InfraNode

Callook.info is a free, keyless lookup service for FCC-licensed US amateur radio callsigns, returning license status, operator class, name, and registered address as either JSON or XML. A live request for a real callsign returns a wildcard Access-Control-Allow-Origin header with no authentication required, confirming it's safe to call directly from browser code.

InfraNode unifies open data for dozens of German cities into a single versioned REST API, covering weather, air quality, EV charging, public-transit departures, demographics, and dozens of other civic datasets. Every endpoint is keyless and rate-limited per IP rather than gated behind a subscription ("Die API ist offen und braucht keinen API-Key"), with an OpenAPI spec and Postman collection published for quick integration. The project is open source (Apache-2.0) and runs on a server in Germany with no ads.