VPNs are a powerful tool for users looking to surf the web privately, but they are also often used by hackers and fraudsters to obscure their activities. For businesses that rely on accurate user location data for ad targeting, content delivery, or security systems, VPN detection is critical to ensure privacy is preserved and malicious traffic is flagged and blocked.

There are many ways to VPN detection service, from basic methods like comparing the browser timezone against the IP time zone to more advanced techniques using TCP/IP fingerprinting and other network data. However, no method is 100% accurate in detecting all VPN connections and each has its own false positive rates.

The best solution for websites is to use a reliable VPN detection service that utilizes both machine learning and probability theory with dynamic checks using large datasets. This approach provides a real number value between 0 and 1 that indicates how likely an IP address is a VPN / proxy / hosting or bad IP based on our dynamic lists. Billions of records are parsed each month to keep the detection system up to date and ensure the highest detection accuracy possible.

How Proxy Detection Solutions Work Behind the Scenes

Using a service like GetIPIntel’s API enables websites to detect VPNs and other proxy servers through a simple HTTP request. The API uses a proprietary database with tens of millions of known VPN and proxy servers that are regularly updated. The query returns a probability value between 0 and 1 that indicates how probable it is that the requested IP address is a VPN or proxy server based on a combination of factors including DNS queries, timezone mismatch, and other network characteristics.