Using a VPN? Find out whether it is leaking data with this set of tools

Man using desktop PC
Återställ förlorad data och undvik stress (Image credit: Gorodenkoff / Shutterstock)

If you’re keen to beef up the tools in your online privacy arsenal there’s never been a better time to get armed with a Virtual Private Network, or VPN as it’s more commonly referred to. Choosing one of the best VPNs can help to keep you safe and secure when you’re online, especially if you spend a lot of time browsing the internet. 

Selecting a popular and reliable brand of VPN not only provides you with a secure and affordable means to securely stay connected to the web, but it can be really easy to configure too. While all VPNs are essentially a variation on the theme, some offer more features than ever and often they can be setup with nothing more than a couple of clicks.

The added value VPN

You’ll generally need to pay a nominal subscription fee to enjoy what the best VPNs have to offer, but it can be money well spent. As an example, if you sign up with ExpressVPN, one of the best-known and hugely popular options out there, you’ll find you get much more than the software itself. 

In fact, ExpressVPN are experts in the Virtual Private Network field and, as a result, have lots of knowledge to share with you if you’re keen to dip a toe further into the world of online privacy. A while ago now, ExpressVPN unveiled a suite of free online security tools that allowed consumers to test if their VPN provider was leaking data. 

Leaks occur if a VPN fails at protecting a device's DNS queries (despite the fact that the rest of the traffic is safe behind a VPN). This can result in ISPs or other third parties having access to the consumer's browsing history or app usage, rendering a VPN essentially useless. Today, the demand for tools like this is greater than ever and the good news is ExpressVPN still has plenty of help at hand.

Open source VPN assistance

The tools were originally made available as open source, under the MIT License. At the time, back in 2017, ExpressVPN said they were also the first-ever public tools to enable automatic leak testing. 

Back then, the company explained the tools could cover a wide range of potential leaks, like having an IP address discovered through a WebRTC leak, exposing browsing activity when a user switches between networks, or exposing data in case the VPN software crashes or can't reach the server. Similar issues still exist, which is why what ExpressVPN has been offering over the years remains as pertinent today as it did back then. 

Today, ExpressVPN still has its suite of tools you can use, which are free and open source. They can be called upon to detect the different types of leaks that can affect VPNs. This includes analysing IP address leaks, IP traffic leaks, DNS leaks and WebTRC leaks, as well as BitTorrent leaks too. What’s more, ExpressVPN offers up the ability to discover leaks that have resulted from unstable network connections along with leaks occurring due to VPN servers being unreachable. It’s a comprehensive box of tricks.

A health check for your VPN

Professor Andrew Jones, Director of the Cyber Security Centre at the University of Hertfordshire, believes such tools are important because of the trust consumers are putting in VPN services. 

"While people are increasingly using the internet in all aspects of their lives, they are also, as a result of the ongoing publicity, becoming more aware of the risks to their privacy. People have reasonably assumed that the use of a VPN was offering some degree of protection to their online privacy, however, this research has shown that there are significant potential weaknesses in a number of the tools that we use and as a result, they are not as well protected as they believe,” he said.  

“Users, rightly or wrongly, trust products that are designed to help them protect their information and when these are shown to have weaknesses, the impact can be significant.”

To learn more about leaks and how this tool can detect them, visit this link and scroll to the very bottom.

Leak testing tools

Online security never stands still and there’s a constant need to keep on top of the latest developments. The folks at ExpressVPN have always underlined the ongoing need for rigorous and regular testing to ensure its services remain as robust as ever. Being able to test for leaks is part of that and the company still maintains its options if you’re keen to carry out your own checks for added privacy and security.

The ExpressVPN team originally developed its leak testing tools for use internally, but ever keen to boost privacy and security throughout the VPN world, the company has released the tools for free. It’s all open source too, which means that anyone who has a vested interest in the world of VPNs can dip in and assess their vulnerability to leaks, along with evaluating their preferred VPN as an added bonus. 

ExpressVPN has every intention of continuing with the provision of these link testing tools and has plans to keep developing them too. That’s great news for those of us who make use of a VPN and in whatever context, be it work, leisure or both. Take the ExpressVPN leak testing toolkit for a spin – you could be surprised at the results.

We've listed the best business VPN.

TOPICS
Rob Clymo

Rob Clymo has been a tech journalist for more years than he can actually remember, having started out in the wacky world of print magazines before discovering the power of the internet. Since he's been all-digital he has run the Innovation channel during a few years at Microsoft as well as turning out regular news, reviews, features and other content for the likes of TechRadar, TechRadar Pro, Tom's Guide, Fit&Well, Gizmodo, Shortlist, Automotive Interiors World, Automotive Testing Technology International, Future of Transportation and Electric & Hybrid Vehicle Technology International. In the rare moments he's not working he's usually out and about on one of numerous e-bikes in his collection.

With contributions from
Read more
best Secure VPN
Secure VPN providers 2025: safe options for the best security and encryption
Person using a phone and laptop in a cafe.
Best privacy tool and anonymous browser of 2025
Abstract illustration of a young woman looking at a smartphone, as large eyes peek through from her hair
Want to hit restart on your online presence? Here's 5 tools you need to stay truly private online
VPN apps running on various devices during TechRadar's testing
The best VPN service 2025
Outlook Calendar on a Tablet
What we learned from VPNs in 2024
Laptop in home office with stylised letters VPN on the screen
The best Windows VPN for PC in 2025
Latest in VPN Privacy & Security
PrivadoVPN running on an iPhone during TechRadar's VPN tests
Why PrivadoVPN Free is still the best free VPN for streaming
Homepage of CloudFlare website on the display of PC, url - CloudFlare.com.
"Network blocking is never going to be the solution" – Cloudflare slams anti-piracy tactics
Panels at RightsCon 2025 during a press briefing about the latest Access Now report of internet shutdowns
2024 was the worst year on record for internet freedoms – again
Vector illustration of the word Censored in a glitch distorted style
Google, Apple, and internet restriction – how Big Tech is making censorship "much worse" according to experts
Google Chrome logo on a mobile phone's screen
Why you need a VPN browser extension
Google TV onscreen interface showing streaming apps
Why do streaming services geo-restrict content?
Latest in Features
Lady Gaga sat at a press conference table for Spotify's fan event
Spotify’s press conference with Lady Gaga shows that music streaming services really do think about the fans after all
Sterling K. Brown as Agent Xavier Collins in Paradise
I'm relieved that Paradise season 2 has been confirmed after that mind-blowing finale
Peter looks to the side with the city skyline behind him in The Night Agent season 2
3 Netflix shows I stopped watching and wouldn't go back to
The player attacks an enemy in Judgement.
The latest PlayStation sale is here, and these are the five games under $15 / £15 I've got in my basket
PrivadoVPN running on an iPhone during TechRadar's VPN tests
Why PrivadoVPN Free is still the best free VPN for streaming
The Blades of Fire key art.
MercurySteam CEO discusses upcoming new IP Blades of Fire: 'We love third person action adventure games and we wanted to revisit the genre'