About Us

cyberTell is a Swiss cyber security and intelligence project dedicated to protecting internet users. We’re currently in beta mode, which means that we offer some of our new features for free and for a limited time only. For two weeks, you can use this page to check if your Swiss phone number was part of the facebook data breach. Compromised data included phone numbers, email addresses, employers, date of birth, relationship status, location.

What is a data breach?

A data breach happens when criminals steal sensitive information from websites, usually online accounts. It is often a result of hackers exploiting a weakness in the website’s security. Data breaches can also occur when account data gets leaked by accident or on purpose.

How can I use cyberTell?

If you have a Swiss phone number, you can use cyberTell to check whether your data was part of’s data breach in 2019. Since this is a beta release, we only verify Swiss phone numbers, but we might add support for additional countries in the future. For updates on cyberTell, follow us on

2019? It’s 2021!

Depending on the nature of a cyber attack, it can take months or even years for the data to appear on the dark web. Once cyberTell discovers a data breach, we verify the authenticity and start warning users about their exposure. On average, cyberTell identifies data breaches around two weeks after they happen.

Does the cyberTell app keep my phone number?

No. When you enter your phone number in the search bar, your browser will transform your phone number into a hash, which will then be sent to cyberTell and compared to the hash of the data that was exposed in the dark web. If there is a match, you’ll know that your data was part of the breach.

My data was leaked. So what?

Entire networks of criminals rely on stolen and compromised data. They can simply try to take over your accounts and cause severe damage to you and others or they can process the data further and use it to steal identities, build SPAM systems, develop computer programs that will abuse your data in countless other ways such as credential stuffing and fraud.

But there are others...

Yes. Monitoring activity on the dark web is not a new discipline, and we’re glad it isn’t. However, the cyberTell team understood that a radically different approach is needed to improve internet and account safety for users so we developed unique and scalable software to better, faster and more accurately identify compromised information and inform users and law enforcement.

Contact Us


Zurich, Switzerland