IP address
The numeric label that identifies a device on a network and is the address a proxy substitutes for your own.
An IP address is the return address on your traffic. Without one there is nowhere to send the reply, so every request you make carries yours and every server you contact sees it. That makes it the most revealing single fact about where your traffic came from, and it is revealed by necessity rather than by any tracking decision: the internet cannot function without it.
There are two versions in service. IPv4 is the familiar dotted form like 203.0.113.42, a 32-bit number giving roughly 4.3 billion possibilities, which sounded limitless in the 1980s and ran out in practice years ago. IPv6 is the long hexadecimal form, 128 bits, and the address space is large enough that exhaustion stops being a concern. The scarcity of the first is the reason for most of the workarounds described below.
Addresses also split into public and private. The ranges beginning 10., 172.16 to 172.31 and 192.168 are private: they are reused inside millions of separate networks and are not routable on the open internet. The address your laptop reports to itself is almost always one of these, which is why it never matches what a website says you are. Your public address belongs to your router, and everything in your home shares it.
What a destination actually learns from your address is narrower than people assume, and worth stating precisely. It learns the owning organisation, reliably, because that register is public. It learns a rough location, with country accuracy that is usually good and city accuracy that is frequently wrong by a wide margin, since geolocation is inference from registration and routing rather than a measurement. And it learns the network TYPE, which is the part that decides how you are treated: home broadband, hosting provider, mobile carrier, corporate range.
That last point is the one that matters most for proxy work. The same numeric string can identify a household, a rack or a phone, and the ownership behind it does far more work than the number. Two addresses can be equally clean and be treated completely differently because one resolves to a consumer ISP and the other to a cloud provider.
Address scarcity also means an address rarely maps to a person. Carrier-grade NAT puts large numbers of mobile subscribers behind one public IP, and ordinary home routers put every device in a house behind one. So one address can represent hundreds of people, which is exactly why blanket blocking is expensive for a site and why mobile addresses get treated so gently.
A proxy exists to substitute this one label. The destination sees the proxy's address instead of yours, and every inference it makes about location, network and trust is made from the substitute. Nothing else about your request changes, which is why the address is necessary and not sufficient: swap it and everything above it, from your TLS fingerprint to your browser's reported time zone, still tells its own story.
How it works
- 1.Your device sends a request; your router replaces the private source address with your public one.
- 2.The destination reads that public address from the packet and can act on it before parsing anything else.
- 3.It looks the address up: which organisation owns the range, and what kind of network it is.
- 4.It geolocates it, usually accurately at country level and much less so at city level.
- 5.It checks the address against reputation data, its own history, and known-proxy lists.
- 6.Only then does it consider the request itself. With a proxy in place, every one of these steps runs against the proxy's address instead of yours.
How HProxy handles it
Everything our checker reports about a free entry is really a set of claims about one address: who owns it, where it geolocates, what it leaks in headers, and whether it answers at all right now. We publish those per address rather than as a single verdict, because the useful question is never just whether an IP works.
Frequently asked questions
Why does my computer show a different IP than what websites see?
Because your device reports its private address and websites see your public one. Anything starting 192.168, 10. or 172.16 to 172.31 is a private address, reused inside millions of separate networks and not routable on the open internet. Your router holds the single public address, and every device in your home shares it.
How accurate is IP geolocation?
Good at country level, unreliable at city level. Geolocation is inference from registration records and routing behaviour rather than a measurement, so it commonly places a visitor in the city where their provider registered the range rather than where they actually are, which can be hundreds of kilometres out. Treat country as dependable and anything finer as a hint.
Can two people have the same IP address?
Routinely, and on mobile networks at enormous scale. Every device in one household shares that home's public address, and carrier-grade NAT puts many mobile subscribers behind a single public IP. An address identifies a connection point, not a person, which is precisely why blocking one can affect many innocent users.
Does changing my IP make me anonymous?
No. It changes the most obvious identifier and leaves every other one intact. Your browser fingerprint, your TLS handshake, your cookies, your reported time zone and your behaviour all persist across an address change, and a site correlating them sees one visitor wearing different addresses, which is more conspicuous than staying put. An address swap is one layer, not a disguise.
What is the difference between IPv4 and IPv6 for proxies?
Mostly availability and acceptance. IPv4 is scarce and expensive, which is why almost all proxy supply is IPv4 and why prices reflect that scarcity. IPv6 is abundant and cheap, but many destinations either do not serve it at all or treat large IPv6 blocks with more suspicion because obtaining a great many addresses is trivial. Cheap per address is not the same as useful.
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