VPN detection guides
Practical, vendor-neutral guides for fraud teams, ad-ops, support, and developers. Copy-paste code samples and decision frameworks — no marketing fluff.
How to detect VPN users on your website
Implementation walkthrough with copy-paste code in Node.js, Python, Go, PHP, and Cloudflare Workers. Server-side, edge, and client-side patterns.
Python integration guide — IPLogs API end-to-end
Production Python integration: /v1/check with requests or httpx, per-IP caching, /v1/bulk-check, retries, TypedDict response, vitest-style tests with responses mocks.
Node.js integration guide — TypeScript + Express
Express middleware that runs IPLogs on every request, TypeScript response types, fetch with AbortSignal.timeout, LRU or Redis cache, batch with /v1/bulk-check, vitest stubs.
Go integration guide — net/http + context
Stdlib-only Go integration: typed verdict, http.Client with context.WithTimeout, ClientIP from a trusted proxy, sync.Map per-IP cache, /v1/bulk-check, httptest-backed tests.
Client-side VPN detection signals (and their limits)
What the browser actually exposes about VPN use: WebRTC ICE candidates, JA3/JA4 TLS fingerprints, timezone vs IP geo. When client signals help and when they mislead.
How to block VPN, proxy, and Tor traffic
Production-tested rules for Cloudflare WAF, Nginx, Caddy, and Stripe Radar. Includes the exact ASN list, false-positive playbook, and step-up alternatives to hard blocks.
Why complete VPN blocking can't be a compliance solution
The technical reality of VPN blocklists: exits rotate, residential proxies look like real users, anti-censorship protocols evolve faster than rules. What multi-signal verdicts can and can't deliver.
VPN regulations: a framework for evaluating compliance
How to think about VPN legality by jurisdiction without trusting stale lists. Four categories of regulation, authoritative sources to consult, and the technical limits of IP detection for compliance.
AI and ML in VPN detection — what works, what's hype
Honest engineer's view of where machine learning helps in IP intelligence and where the marketing exceeds the substance. Why IPLogs ships deterministic weighted signals rather than a trained model.
Ethics and privacy in IP intelligence
What an IP-intelligence service should collect, expose, and refuse. IPLogs' principles: no signup, no tracking, open methodology, published false-positive rate, and per-action policy that minimises collateral harm.
Why is my IP flagged as a VPN?
Twelve real-world reasons your IP shows as a VPN/proxy when you're not on one — CGNAT, mobile carriers, iCloud Private Relay, Cloudflare WARP, residential proxies running on neighbour devices, and how to dispute.
Residential vs datacenter IPs — how to tell the difference
What residential proxy traffic actually looks like to a server, why ASN classification alone isn't enough, and the additional signals (peer count, BGP single-homing, RTT) that separate the two.