
Real-time Geolocation & Reverse IP Lookup REST API.
ipapi.com API is a free Geocoding API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Free IP to geolocation REST API supporting IPv4 or IPv6 GeoIP and reverse IP lookup using JSON and XML in PHP, JavaScript, Node, Python, Java, and more.
Details from ipapi.com.

Unified API suite · now live
Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
IP Geolocation API. Collecting data from multiple sources
The ipapi.com API is provided by IPAPI (ipapi.com). Free IP to geolocation REST API supporting IPv4 or IPv6 GeoIP and reverse IP lookup using JSON and XML in PHP, JavaScript, Node, Python, Java, and more.
Yes. The ipapi.com 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.
Yes. The ipapi.com API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the ipapi.com API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The ipapi.com API is served over HTTPS, so it's safe to use in production.