Turn a VPN on, and within seconds your public IP address changes. But what's actually happening behind the scenes, how real is that change, and what does it not protect? This guide follows a request step by step, shows who can see what with and without a VPN, explains how websites still recognise VPN addresses, and gives you a quick way to confirm that yours is doing its job.
What a VPN actually does to your IP
A VPN (Virtual Private Network) creates an encrypted tunnel between your device and a server somewhere else in the world. All of your internet traffic first passes through that tunnel and exits from the VPN server. A simplified view:
Without VPN: your device -> your ISP -> website (website sees your ISP's IP)
With VPN: your device -> [encrypted tunnel] -> VPN server -> website
(website sees 198.51.100.7, the VPN server's IP)As a result:
- Websites and services you visit see the VPN server's IP address — not your real one.
- The location shown also reflects the VPN server's location, not your actual location.
- Your ISP can still see that you're connected to a VPN server, but the traffic content itself is encrypted and unreadable.
Who sees what
| Who | Without a VPN | With a VPN |
|---|---|---|
| The website | Your public IP, ISP and rough location | The VPN server's IP, ISP (the VPN host) and location |
| Your ISP | Which sites you contact | Only that you talk to a VPN server, and how much data |
| Someone on the same Wi-Fi | Unencrypted traffic and the sites you contact | Encrypted traffic to the VPN server |
| The VPN provider | — | Your real IP and, technically, the sites you visit |
In other words, a VPN moves trust from your ISP to your VPN provider; it does not remove it.
How the connection works (briefly)
- The VPN app authenticates with the server and agrees on encryption keys.
- The app adds a virtual network adapter and sends your traffic into it, encrypted. Your normal local IP stays the same (private vs public IP).
- The server decrypts the traffic and forwards it to the destination using its own public address, then sends the replies back through the tunnel.
Common protocols are WireGuard (modern and fast), OpenVPN (mature and flexible) and IKEv2 (good on phones when switching networks). A kill switch blocks all traffic if the tunnel drops, so your real IP does not slip out.
How is a VPN different from a proxy?
Both change your apparent IP address, but a proxy usually only routes traffic from one specific app or browser and often doesn't encrypt it, while a VPN routes your device's entire traffic through an encrypted tunnel. That's why a VPN is generally considered more reliable for privacy than a free proxy. A full comparison with Tor is in Proxy vs VPN vs Tor.
How do websites detect that an IP belongs to a VPN?
Specialized services maintain lists of IP ranges belonging to known datacenters and VPN providers. When your IP address appears on one of those lists, it gets flagged as "datacenter/VPN." Signs they look for:
- A hosting-company network. The address belongs to a datacenter rather than a home ISP (see what an ASN is).
- Many users on one address. VPN servers share an IP among hundreds of people, and some of them behave badly, which can earn CAPTCHAs or blocks (IP blacklists).
- Mismatches. A browser language or time zone that does not fit the IP's country is a hint.
- Leaks. DNS requests or WebRTC that reveal your real address (see the VPN leak test).
You can try the detection on your own connection right now: open the Show-IP.ir homepage and check the "Security Check" section — if a VPN is active, "VPN / Datacenter" will usually flip to "Yes." Remember that Show-IP.ir reports on the address you are connecting from, so it checks your own VPN; it is not a tool for looking up other people's addresses.
What changes and what stays the same
| Item | Changes with a VPN? |
|---|---|
| Public IP, country, city, ISP/ASN seen by sites | Yes — they become the VPN server's |
| Local IP (192.168.x.x) and MAC address | No |
| Browser cookies, logins, fingerprint | No |
| Speed and ping | Usually a bit worse; sometimes better on a well-chosen route |
| DNS | Should go through the VPN; check for leaks |
Does a VPN completely hide your IP address?
A VPN hides your real address from the websites you visit, but that's not the same as being completely anonymous — your VPN provider can, in theory, still see your connection unless it has a genuine no-log policy, and logging in to accounts still identifies you. For a full comparison of ways to hide your IP — including VPN, Tor, and proxies — read How to Hide Your IP Address.
Quick test: is my VPN changing my IP?
- Open Show-IP.ir with the VPN off and note the IP, country and ISP.
- Connect the VPN and refresh. The IP, country and ISP should all be different.
- Run the leak check once, and again after you switch servers or networks.
Frequently asked
Does a VPN give me a static IP?
Usually not: you share a server address with other users. Some providers sell a dedicated IP for an extra fee, which is useful for allow-lists and avoiding shared-IP CAPTCHAs.
Will a VPN lower my ping in games?
Rarely, and only when your ISP's route is bad. Normally it adds a little latency; see reducing ping.
Can a VPN change my IP to a particular city?
It changes it to where the server is. Location databases may still place a server inaccurately (geolocation accuracy).
Key takeaways
- A VPN replaces your real IP address with the VPN server's address and encrypts your traffic between you and the server.
- The location shown reflects the VPN server's location, not your actual one.
- Your VPN provider can see what your ISP no longer sees, so choose one you trust.
- Services can detect a VPN connection by checking known IP ranges, and leaks can still expose you.
- You can see your IP change and VPN detection status right now on Show-IP.ir.