Check first to which server IP points the URL. And then check the IP address with an whois (for example
https://www.heise.de/netze/tools/whois/)
I would not trust a mixer which server IP is in the US. The US is against privacy and is treating mixer owner like criminals
I'm not sure what you want to achieve with this, but do you know anything about the Cloudflare service for example?
Cloudflare is only a firewall protection between the server and the end-user or the visitor. Each of the services that use CF can be hosted anywhere and the use of CF does not mean that the service is located in the US.
Ordinary whois tools are not enough to find where a certain server is located.
