PGA Tour golf since 2001: leaderboards, hole-by-hole scores, courses, ratings and major winner odds.
BirdieAPI is a free Sports & Fitness API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.
Full API reference for BirdieAPI. 14 golf data endpoints with parameters, example requests, and response shapes.
Details from birdieapi.com.

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The BirdieAPI is provided by BirdieAPI (birdieapi.com). Full API reference for BirdieAPI. 14 golf data endpoints with parameters, example requests, and response shapes.
Yes. The BirdieAPI is listed in the Sports & Fitness category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The BirdieAPI uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The BirdieAPI supports CORS, so front-end JavaScript can call it directly.
Yes. The BirdieAPI is served over HTTPS, so it's safe to use in production.