Unlimited free IP Address API with useful information.
IPGEO API is a free Geocoding API that requires no API key, is served over HTTPS and has unconfirmed CORS support.

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 with ASN, timezone, currency and threat data, 5,000 keyless calls a day
Free Geolocation tools and APIs for country, region, city and time zone lookup by IP address
Yes. The IPGEO 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 IPGEO API requires no authentication, so you can start making requests without signing up.
CORS support for the IPGEO API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The IPGEO API is served over HTTPS, so it's safe to use in production.