What Is a VPN and How Does It Work?

A VPN, or Virtual Private Network, is a service that creates an encrypted tunnel between your device and the internet. When you connect to a VPN, all of your internet traffic is routed through this secure tunnel to a VPN server before reaching the public internet. This does two critical things: it encrypts your data so nobody between you and the VPN server can read it, and it masks your real IP address so websites see the VPN server's address instead of yours.

How VPN Encryption Works

Think of the internet without a VPN like sending a postcard through the mail. Anyone who handles it along the way -- your mail carrier, the sorting facility, the delivery person -- can read what you wrote. Your ISP, the WiFi network operator, and anyone on the same network can see exactly what you are doing online.

A VPN turns that postcard into a sealed, locked box. Your device encrypts every piece of data before it leaves, creating what is called a 'tunnel.' This tunnel uses military-grade encryption -- typically AES-256 or ChaCha20 -- the same standards used by governments and banks. Even if someone intercepts your data in transit, they would see nothing but meaningless scrambled characters.

The encryption process works like this: your VPN app on your device takes your internet traffic, encrypts it using a cryptographic key that only your device and the VPN server share, wraps it in a new packet addressed to the VPN server, and sends it through your normal internet connection. The VPN server receives the encrypted packet, decrypts it, and forwards your original request to the destination website. The website's response travels back through the same process in reverse.

What a VPN Hides

Understanding what a VPN does and does not hide is crucial. A VPN is powerful, but it is not invisibility.

Your IP Address

Your IP address is like your home address on the internet. Every website you visit can see it, and it reveals your approximate physical location (usually accurate to the city level), your ISP, and can be used to track your browsing across websites. A VPN replaces your real IP with the VPN server's IP, so websites see a shared address used by thousands of other VPN users. This makes it effectively impossible to single you out based on IP alone.

Your Browsing Activity

Without a VPN, your ISP can see every website you visit, every search you make, and every file you download. In the US, ISPs are legally allowed to collect and sell this data to advertisers. In the UK, ISPs are required to retain your browsing history for 12 months under the Investigatory Powers Act. A VPN encrypts all of this, making it invisible to your ISP.

Your Physical Location

Because websites see the VPN server's IP instead of yours, they cannot determine your real physical location from your IP address. This is how people use VPNs to access streaming content from other countries -- if you connect to a UK VPN server, Netflix thinks you are in the UK.

What a VPN Does NOT Hide

Accounts You Are Logged Into

If you are logged into Google, Facebook, Amazon, or any other account, those services know who you are regardless of your IP address. Google does not need your IP to track you -- your Google account ties all your activity together. A VPN hides your IP but does not make you anonymous if you are logged into identifiable accounts.

Cookies and Browser Fingerprinting

Websites use cookies (small files stored in your browser) and browser fingerprinting (collecting details about your browser, screen size, installed fonts, etc.) to track you. These methods work independently of your IP address. A VPN does not block cookies or change your browser fingerprint. For that, you need browser privacy extensions, incognito mode, or a privacy-focused browser like Firefox with strict tracking protection.

Data You Voluntarily Share

If you type your name, email, address, or phone number into a website form, a VPN cannot undo that. The VPN encrypts the transmission, but the website still receives the data you submitted.

When You Need a VPN

Public WiFi

Coffee shops, airports, hotels, and any open WiFi network are prime hunting grounds for data interception. On an unencrypted network, anyone with basic tools can see your traffic. A VPN makes public WiFi safe by encrypting everything before it leaves your device.

Streaming Content From Other Countries

Netflix, Hulu, BBC iPlayer, and other streaming services restrict content by region. A VPN lets you connect to a server in another country and access that country's content library. This is one of the most popular VPN use cases.

Privacy From Your ISP

Your ISP sees everything you do online. In many countries, they are legally required to log this data, and in the US, they can sell it. A VPN prevents your ISP from seeing anything beyond the fact that you are connected to a VPN server.

Traveling or Working Remotely

When you travel, you connect to unfamiliar networks in hotels, airports, and co-working spaces. A VPN keeps your connection secure regardless of where you are. If you travel to countries with internet censorship (China, Russia, Iran), a VPN can help you access blocked websites and services.

When You Don't Need a VPN

You probably do not need a VPN if you are already on a trusted home network with a secure router and you are not concerned about ISP data collection. VPNs add a small amount of latency to your connection, so for competitive online gaming or video conferencing where every millisecond counts, a VPN may add unwanted lag. If you are just browsing HTTPS websites on your home WiFi, the websites themselves are already encrypted end-to-end -- a VPN adds an extra layer but the marginal benefit is smaller.

How to Get Started

Choosing a VPN can feel overwhelming. The most important factors are: a verified no-logs policy (proven by independent audit), fast speeds (WireGuard protocol support), and a jurisdiction outside major surveillance alliances. Our rankings evaluate every VPN on these criteria and more.