One option is ipdata, which offers a full-featured IP Geolocation API. The service offers a broad range of data including geolocation, threat intelligence feeds, proxy and VPN detection, and more. It can be used to send users to the correct website based on their location, and it's a good option for content localization and geographic restrictions.
Another option is IPLocate. IPLocate handles more than 400 million requests per day and offers features like personalized app functionality, user redirection and fraud prevention. It's a good option if you need a high-volume, fast and secure service to send users to country-specific sites or landing pages.
If you want something more flexible, Geniuslink offers a smart URL shortener that can send users to different destinations based on factors like device, operating system and country. The service also offers advanced analytics and other marketing tools, so it's a good option for optimizing user redirects and maximizing revenue.
Finally, ipapi offers detailed IP geolocation data in a variety of formats, including JSON and XML. It offers fast and scalable IP lookups, secure encryption and high availability. It's good for customizing website content and sending visitors to region-specific sites, and it offers flexible pricing options depending on your needs.