Can Sites Detect Your VPN or Proxy?
We look your address up the way a site would - in the lists of hosting and proxy addresses, and by the name of its network - then compare what two independent sources see, and your browser’s timezone with your address’s.
How Do Sites Detect VPNs and Proxies?
Websites have several ways to classify a connection: IP reputation lists flag datacenter, hosting and proxy addresses, network names give some VPN operators away, Tor exit node lists are public, and a browser timezone that does not fit the address’s location is a contradiction a site can notice. Services like Netflix, banking sites, and government portals block addresses that fail such checks.
Detection Methods Used Here
- ip-api.com, through our server: its
hostingandproxylists, and whether the network is named for a VPN - Network name, from ipapi.co: the operator’s name compared with names of VPN and hosting operators
- Two-source comparison: the address our server saw against the one ipapi.co saw, within the same IP family - an IPv4 and an IPv6 address always differ, so they are not compared
- Timezone comparison: your browser’s timezone against the timezone of your address, by continent
A lookup that does not answer is reported as not measured, and decides nothing. Tor is not checked here: the Tor Project’s check service does not answer requests made from other sites’ pages, so a test running in your browser cannot ask it. Open check.torproject.org itself to see whether you are connected through Tor.
VPN & Proxy Detection Test - FAQ
Everything you need to know about VPN and proxy detection, and how websites identify anonymous connections.
Can websites detect if I'm using a VPN?
Many can try. Lists of datacenter, hosting, proxy and VPN address ranges exist, and a site can check your address against one; how accurate those lists are has not been measured here. What our own lab has measured is how two providers fare against one of them: every Proton VPN (free tier) and Mullvad exit it tested through Dutch servers was listed as hosting by ip-api.com, the lookup this page uses, and most were listed as proxies too. Beyond the address, a browser timezone that does not fit your VPN exit's location is another contradiction a site can compare.
How does Tor exit node detection work?
The Tor Project publicly publishes a list of all active exit node IP addresses. Any website can query this list - either directly or via the official check.torproject.org API - to instantly determine if an incoming connection is coming from the Tor network. This means using Tor does not provide anonymity from the fact that you're using Tor, even if it hides your real IP. This page does not check it: the Tor Project's check service does not answer requests made from other sites' pages, so a test running in your browser cannot ask it. Open check.torproject.org itself to see whether you are connected through Tor.
What is an ASN and can it give a VPN away?
An ASN (Autonomous System Number) is a unique identifier assigned to networks on the internet. Every IP address belongs to an ASN, and ASN names are publicly readable. Some VPN exits sit on networks registered in the provider's own name - our lab has seen Mullvad exits on Mullvad VPN AB - and a name check finds those. VPN exits can sit on rented hosting networks whose names say nothing about a VPN: the lab has seen Mullvad on 31173 Services and DataCamp, and Proton VPN's free tier on Netid and NForce. A name check misses those, and the hosting lists are what flag them. Residential proxy networks route traffic through home connections, whose addresses are on consumer networks that neither check flags.
What is split tunneling and how is it detected?
Split tunneling is a VPN feature that routes only some of your traffic through the VPN, while other traffic uses your real IP connection. Our consistency check compares your address as seen by two independent sources. Two different addresses of the same family can mean split tunneling, a transparent proxy, or a misconfigured VPN. An IPv4 and an IPv6 address always differ, which is why a connection with both is not compared across them: which family a site sees is up to the browser, not a sign of a split tunnel.
Which VPNs are hardest to detect?
Ones whose exit addresses are not on hosting or proxy lists - residential addresses are built for that, because they belong to home connections rather than datacenters. The two providers our lab measures are not in that group: every Proton VPN (free tier) and Mullvad exit it tested was listed as hosting, all of Proton's and about three in four of Mullvad's were listed as proxies too, as of early October 2026. Whatever the address, a browser timezone, language or WebRTC address that does not fit the VPN's exit is another thing a site can compare.
Why does Netflix block VPNs?
Netflix blocks VPNs because its content licensing agreements are geo-restricted - their licences are per country, so certain shows can only be shown in certain countries. When users bypass these restrictions via VPN, Netflix risks losing content deals. They use multiple detection methods: datacenter IP blacklists and ASN-based VPN detection. Some VPN providers with residential IPs and obfuscated servers can bypass Netflix blocks, but this is a constant arms race.
Is using Tor illegal?
Using Tor is legal in most countries. Tor is used by journalists, activists, whistleblowers, and privacy-conscious individuals to protect their communications. However, some countries (China, Russia, Iran, Belarus) actively block or restrict Tor. The Tor Browser is developed by the non-profit Tor Project and is built on Firefox. What you do while using Tor is subject to the same laws as normal internet use - Tor does not provide a legal exemption for illegal activities.