Find location with IP address or domain.
ip-api is a free Geocoding API that requires no API key, is only available over HTTP and has unconfirmed CORS support.
Free IP Geolocation API - lookup any IP address
Details from ip-api.com.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
The ip-api is provided by IP-API.com (ip-api.com). Free IP Geolocation API - lookup any IP address
Yes. The ip-api is listed in the Geocoding 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.
No. The ip-api requires no authentication, so you can start making requests without signing up.
CORS support for the ip-api is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
No. The ip-api is only available over plain HTTP, which browsers block on HTTPS sites. Call it from a server instead.