Deezer vs Radio Browser

Deezer's REST API serves the catalog metadata behind the streaming app: tracks, albums, artists, playlists, charts, and full-text search. Unusually for a major streaming service its read endpoints are fully keyless — a plain GET against api.deezer.com returns real track data with no App ID, key, or token at all — while OAuth is reserved for endpoints that act on a user's own account, such as favorites or the activity feed. Responses can be requested as either JSON or XML via an output query parameter, and the API is free to use within Deezer's terms.

Radio Browser is a free, keyless, community-maintained directory of internet radio stations — over 60,000 of them — with search, tagging by genre/country/language, click-tracking, and ready-to-play M3U playlists for any station. It's fully open source, mirrored across several independently-run servers behind a round-robin DNS entry point, and its maintainers explicitly ask API consumers to pick a random mirror rather than hammer one instance. Responses are available as JSON or XML, with a dedicated M3U format for playlist endpoints.