How VPN detection works
Services maintain databases of IP ranges used by VPNs, proxies, Tor exit nodes, and cloud hosts. Your IP is matched against those lists.
Websites use similar signals for fraud prevention, geo-licensing, and bot detection — which is why some sites block known VPN IPs.
How to know if your VPN is working
Run this test before and after connecting. Your IP address, location, and ISP should change to match your VPN server.
Pair this check with a DNS leak test and WebRTC leak test — a working VPN should pass all three.
Limitations
New or niche VPN servers may not yet appear in databases. Conversely, shared datacenter IPs are not always VPNs.
Treat results as one data point alongside DNS and WebRTC leak tests.