A website can compare the public address it observes with known network-registration or reputation data to estimate whether traffic may come from a hosting provider, proxy, or VPN. These signals can be incomplete and are not a definitive test of how your device is configured.
What a result can tell you
IP ownership, network type, and provider flags may suggest that an address belongs to a data center or privacy service. They cannot reliably distinguish every VPN, proxy, corporate gateway, mobile carrier, or shared connection.
Use the available lookup
This site does not run an independent proxy-detection or anonymity test. You can inspect approximate provider and network details with the public IP lookup; its information may not identify proxy use.