Accurate VPN, Proxy, Relay and Tor Detection

Websites detect VPN and proxy connections by matching the IP against databases of known anonymizers and analyzing the connection across multiple signal layers. IP blocklist matching compares the incoming IP against lists of known VPN and proxy servers, which is fast but limited because providers rotate IPs daily and residential proxies use consumer ISP addresses that never appear in blocklists. Connection analysis inspects the connection across layers including OS, browser timezone versus IP geolocation, connection-type indicators, and device and browser attributes against network parameters. ShieldLabs uses the multi-layer connection-analysis approach, so it flags anonymized traffic even when the IP is clean and the masking is fresh.

Yes. Residential proxies route traffic through real consumer ISP connections that pass standard blocklist checks, so ShieldLabs identifies them at the network level instead of by IP reputation. ShieldLabs checks device, OS, and network consistency; looks for connection anomalies inconsistent with normal consumer traffic; and checks for cross-layer mismatches between claimed and observed parameters. ShieldLabs returns proxy use as a distinct signal in the API response, so you can score it separately from a clean connection.

A VPN routes traffic through an encrypted tunnel that assigns a new IP address; a proxy forwards requests through an intermediary server without necessarily encrypting the full connection. A VPN uses an encrypted tunnel with a new egress IP, usually commercial infrastructure. A proxy is an intermediary relay (anonymous or web) that forwards requests, often without encryption. ShieldLabs detects both as separate signals, so you can choose a different action for each instead of treating all anonymized traffic the same.

Yes, and it treats Private Relay differently from a commercial VPN, because Relay preserves approximate location while masking only the exact IP. It is identified as its own signal type, not lumped with VPN or proxy, which lets you tell privacy-conscious Apple users apart from genuinely high-risk anonymized traffic. ShieldLabs flags Privacy Relay separately, so you don't penalize legitimate users for a built-in privacy feature.

ShieldLabs detects anonymized connections with 99.9% risk signal detection accuracy by analyzing the connection in real time rather than relying on static IP databases. It evaluates cross-layer mismatches and connection characteristics live, on every visit. Contextual scoring adapts to each platform's traffic profile to keep false positives low. Because detection is signal-based, accuracy holds even as anonymization providers rotate IPs and launch new infrastructure.

Integration takes about 5 minutes: add one JavaScript snippet and analysis starts immediately. Start Free, add your domain in the analytics dashboard, install the snippet on your site, and read results in the analytics dashboard, API, or Webhooks. ShieldLabs returns the first risk score on the very first visit, with no model training or warm-up period.