VPN Guide

The Complete VPN Guide: How VPNs Work, Security, Speed & Choosing a VPN

A practical VPN guide explaining how VPNs work, what they protect, VPN speed and WebRTC leaks, plus how to choose the right VPN.

A VPN can protect your internet connection, hide your public IP address and make public Wi-Fi safer. But choosing the right VPN isn't simply about finding the provider with the most servers or the lowest advertised price.

You need to understand what a VPN actually does, what it doesn't do, how it affects internet speed and which features are genuinely useful.

This guide explains the essentials and points you toward more detailed guides when you want to go deeper.

What Is a VPN?

VPN stands for Virtual Private Network.

A VPN creates an encrypted connection between your device and a VPN server. Instead of sending your internet traffic directly from your device to the websites you're visiting, your traffic first travels through the VPN server.

Without a VPN:

Your device → ISP → Website

With a VPN:

Your device → Encrypted VPN connection → VPN server → Website

The website generally sees the VPN server's IP address rather than your original public IP address.

This can improve privacy and make your connection safer when you're using networks you don't fully trust.

What Does a VPN Actually Do?

A VPN primarily provides three useful benefits.

1. It encrypts your connection

A VPN encrypts traffic between your device and the VPN server.

This is particularly useful when you're connected to networks you don't control, such as hotel, airport, café or other public Wi-Fi.

2. It hides your public IP address

When you connect through a VPN server, websites generally see the server's IP address rather than your normal public IP.

This can also allow you to appear to be connecting from another location.

3. It provides another layer of privacy

Your internet traffic takes a different route through the VPN infrastructure instead of going directly from your device to the destination.

However, a VPN isn't an anonymity tool.

Your accounts, cookies, browser fingerprint, tracking technologies and the information you voluntarily provide to websites can still identify or track you.

What Doesn't a VPN Protect You From?

This is one of the most important things to understand before buying a VPN.

A VPN doesn't automatically protect you from:

Phishing websites
Malware
Viruses
Weak passwords
Stolen credentials
Unsafe downloads
Social engineering
Tracking through accounts and cookies
Giving personal information to a website

Think of a VPN as one security and privacy layer, not a complete cybersecurity solution.

For example, if you receive a fake banking email and enter your password on a phishing website, having a VPN connected won't magically prevent the account from being compromised.

Do You Need a VPN on Public Wi-Fi?

Public Wi-Fi is one of the most practical situations where a VPN can be useful.

When travelling, you may connect to Wi-Fi at:

Airports
Hotels
Restaurants
Cafés
Railway stations
Coworking spaces

You don't necessarily know how the network is configured or who else is connected.

A VPN can encrypt the connection between your device and the VPN server, providing an additional layer of protection.

We've covered this in detail in:

Can a VPN Protect You on Public Wi-Fi?

The important point is that a VPN doesn't make a fake Wi-Fi network legitimate. You should still verify the network name and follow normal security practices.

Does a VPN Slow Down Internet Speed?

It can.

A VPN adds encryption and routes your traffic through another server, so some performance reduction is normal.

The amount of slowdown can vary considerably depending on:

Distance to the VPN server
Server congestion
VPN protocol
Your original connection
Network routing
Device performance
Time of day

A 10% reduction might be barely noticeable on a fast connection, while a much larger reduction could affect streaming, gaming or video calls.

That's why you shouldn't judge a VPN's performance based solely on marketing claims.

Test Your VPN Speed

You can use the BeingOptimist VPN Speed Test to check:

Download speed
Upload speed
Ping
Jitter
IP information
Stability
Overall performance

For a detailed explanation of the testing process, read:

Why Is My VPN So Slow? How to Test and Improve VPN Speed

The basic process is simple:

Test without VPN → connect VPN → test again → compare the results.

Don't rely on one test. Run multiple tests under similar conditions.

What Is Ping and Why Does It Matter?

Download speed gets most of the attention, but it's not the only measurement that matters.

Ping measures latency—the time required for data to travel between your device and the destination.

Lower ping is generally better.

Ping matters particularly for:

Gaming
Video calls
Remote desktop
Interactive applications

A VPN server that is geographically far away can increase latency even if the download speed remains excellent.

What Is Jitter?

Jitter measures variations in latency.

A connection with stable latency is generally preferable for real-time activities such as gaming and video calls.

That's why our VPN Speed Test doesn't focus exclusively on Mbps.

Download + upload + ping + jitter + stability gives you a more useful picture of VPN performance.

Can a VPN Leak Your IP Address?

A properly configured VPN should prevent websites from seeing your normal public IP address.

However, browser-level technologies such as WebRTC deserve attention when you're evaluating privacy.

WebRTC is used by browsers for real-time communication, and depending on browser and network configuration, it can expose network information.

That doesn't mean every WebRTC result is automatically a VPN leak.

The important question is what information is actually being exposed.

Test for WebRTC Exposure

You can use the BeingOptimist WebRTC Leak Test Tool.

The tool checks information including:

Public IP
Private IP
Local IP masking
WebRTC candidates
Candidate types
mDNS status
STUN status
Privacy assessment
Risk level

For example, a result showing that the local IP is masked and no private IP is exposed is very different from a result showing potentially identifying IP information.

Don't judge a WebRTC test simply by seeing technical terms such as HOST or SRFLX. The actual IP exposure and context matter.

Free VPN vs Paid VPN

Free VPNs can be tempting, particularly if you're only looking for occasional protection.

But before choosing one, consider:

How the provider makes money
Its privacy policy
Data collection
Server availability
Speed limitations
Data limits
Supported devices
Security features

A paid VPN isn't automatically trustworthy either.

You still need to evaluate the provider.

We've covered the decision in more detail:

Free VPN vs Paid VPN: When Is Upgrading Worth It?

How Do You Choose a VPN?

Instead of asking:

“Which VPN is the best?”

ask:

“Which VPN is best for what I actually need?”

Here are the features I would consider before subscribing.

1. Server locations

If you need to connect to particular countries, check whether the VPN offers servers in those locations.

2. Speed

Look beyond advertised speeds.

Your actual performance depends on your location, network and chosen server.

3. Privacy policy

Understand what information the provider collects and how it handles your data.

4. Security features

Look for features relevant to your use case, such as a kill switch, DNS leak protection and secure VPN protocols.

5. Device support

Check whether the VPN supports the devices you actually use.

6. Simultaneous connections

If you want to protect a phone, laptop, tablet and other devices, check how many simultaneous connections are included.

7. Price and renewal terms

Don't look only at the introductory price.

Check the renewal price and subscription period before purchasing.

8. Ease of use

A VPN with excellent features isn't very useful if the application is difficult to configure.

VPN for Travel

Travellers have some particularly good reasons to consider a VPN.

You may regularly deal with:

Public Wi-Fi
Hotel networks
Airport networks
Different ISPs
Unfamiliar networks
Location-dependent websites and services

For travellers, I would particularly look at:

Security + server locations + speed + device support + price.

We'll cover this in more detail in our upcoming Best VPN for Travel guide.

VPN vs Proxy

VPNs and proxies can both change the IP address visible to websites, but they aren't the same technology.

A VPN generally operates at the device/network level and creates an encrypted connection to the VPN server.

A proxy typically handles traffic for a particular application or connection and doesn't necessarily provide the same level of encryption or privacy.

If you're trying to decide between the two, our upcoming VPN vs Proxy guide will cover the differences in more detail.

Do You Need a VPN?

Not everyone needs a VPN 24/7.

Your situation matters.

A VPN can make particular sense if you:

Frequently use public Wi-Fi
Travel regularly
Want to hide your public IP from websites
Need to connect through VPN servers in different locations
Want an additional privacy layer
Work remotely on unfamiliar networks

If you're wondering whether the benefits justify paying for a VPN, start with:

Free VPN vs Paid VPN

iTop VPN vs NordVPN

For StackPulse, these are two of the VPN products we're currently covering.

iTop VPN vs NordVPN: Which VPN Is Worth Paying For?

We've also published a dedicated article for readers evaluating iTop VPN:

Is iTop VPN Worth It? Features, Limitations and Paid Plans

And if you're specifically researching NordVPN pricing:

NordVPN Pricing Explained

These articles are designed for readers who are already further along in the buying process.

How to Test a VPN Before Trusting It

You don't have to blindly accept a VPN's marketing claims.

You can perform a few practical checks yourself.

Check 1: Public IP

Connect to the VPN and check whether your visible IP changes.

Check 2: Speed

Compare your connection with the VPN off and on.

Use the BeingOptimist VPN Speed Test.

Check 3: WebRTC

Check whether your browser is exposing potentially identifying network information.

Use the BeingOptimist WebRTC Leak Test.

Check 4: Stability

Repeat your tests.

One excellent result doesn't necessarily mean the VPN will perform consistently.

VPN Features That Actually Matter

VPN marketing can make it difficult to distinguish genuinely useful features from features that simply sound impressive.

For most users, I would prioritize:

Strong encryption → trustworthy privacy practices → reliable connections → useful server locations → good performance → appropriate price.

Features such as huge server counts can be useful, but a larger number doesn't automatically mean a better VPN.

Likewise, the cheapest subscription isn't necessarily the best value.

Frequently Asked Questions

Does a VPN make you completely anonymous?

No. A VPN can hide your IP address from websites and encrypt the connection between your device and the VPN server, but it doesn't eliminate cookies, account-based tracking, browser fingerprinting or other identification methods.

Does a VPN always slow down internet speed?

No. Some performance reduction is common, but the impact varies. A good VPN connection may still be fast enough that you don't notice the difference.

Should I use a VPN on hotel Wi-Fi?

A VPN can provide an additional layer of protection when you're using hotel or other untrusted Wi-Fi networks.

Can a VPN prevent phishing?

No. A VPN doesn't determine whether a website is legitimate. You still need to recognize phishing attempts and verify URLs.

How can I test my VPN?

Start by comparing your internet connection with the VPN disabled and enabled. You can use the BeingOptimist VPN Speed Test for performance and the BeingOptimist WebRTC Leak Test for browser-level IP exposure.

Is a paid VPN better than a free VPN?

Not automatically. But paid services may provide more features, locations, bandwidth and support. Evaluate the provider rather than assuming “paid” automatically means better.

Final Verdict

A VPN is best understood as a privacy and security layer, not a complete cybersecurity solution.

The right VPN depends on what you're trying to accomplish.

If you care about public Wi-Fi protection, look at security features.

If you travel, consider server locations and ease of use.

If performance matters, test download speed, upload speed, ping and jitter.

If browser privacy concerns you, check for WebRTC exposure.

And if you're ready to compare providers, don't rely on one generic “best VPN” list.

Start with the information that matters to you, then use our detailed comparisons and reviews to make the final decision.

Explore the StackPulse VPN guides

And use our free tools:

Affiliate disclosure: StackPulse may earn a commission from qualifying purchases made through affiliate links. Prices, features and offers can change, so check the provider's current terms before subscribing.