Privacy policy

This English translation is provided for convenience. Only the German version is legally binding.

In short

This website uses no cookies (exception: sign-in to the internal area, see section 4), no tracking, no analytics tools and no content or fonts from third parties. All calculators and quizzes (checks, glossary search, guide, calculators, data traffic light, risk class finder, password check, generators) run only in your browser. Your input there is neither stored nor transmitted. Only if you change the display or offline settings yourself does your browser remember this choice locally (see section 5).

1. Controller

The controller for data processing on this website within the meaning of the GDPR is:
Karsten Russo, Eidelstedter Dorfstraße 34, 22527 Hamburg, Germany
Email: info@sicherheitsdenker.de

No data protection officer has been appointed. Please send data protection requests to the address above.

2. Hosting and server log files

This website is hosted by STRATO (Otto-Ostrowski-Straße 7, 10249 Berlin, Germany). When a page is requested, the server processes technically necessary data. It may store it in log files: IP address, date and time, requested page or file, referrer address, browser type and operating system, status code and amount of data transferred.

Purpose and legal basis: Delivery of the website, stability and security, in particular detecting and preventing attacks. The legal basis is Art. 6(1)(f) GDPR (legitimate interest in secure and stable operation).

Storage period: According to the provider, visitors' IP addresses are stored for a maximum of 7 days to detect and prevent attacks. According to its own information, the provider processes the data in data centres in Germany and uses no tracking mechanisms or web analytics on hosted sites. The provider processes the data on my behalf. More information is in STRATO's privacy policy at strato.de/datenschutz.

3. Contact

If you email me or use the contact form, I process your details to answer your request. These are your name, email address, chosen topic and message. Name, email address and message are required in the form so that I can reply.

How the contact form works: Your input is sent to this website's server at STRATO and forwarded to me by email from there. The form does not store your input on the server (no database, no file). To protect against automated spam, the form uses a hidden field and a check of the time taken to fill it in. No cookies are set and no third-party services are used. The form does not evaluate your IP address. As with every page request, it is briefly recorded in the server log files (see section 2). Forwarding by email uses the host's mail infrastructure. Emails are generally not protected against being read by others.

"AI guidance" interest list: If you sign up on the "AI guidance" page, I receive your name and email address in the same way as a contact request. I only use them to inform you when there is an offer. The legal basis is your consent (Art. 6(1)(a) GDPR). You can withdraw it at any time by email, and I will then delete your data.

Legal basis: Art. 6(1)(f) GDPR (legitimate interest in answering requests). For requests aimed at a contract or pre-contractual measures, Art. 6(1)(b) GDPR. Storage period: I delete your message and details from my mailbox once your request has been dealt with and no statutory retention obligations apply.

4. Internal area with sign-in

The internal area is only for people I invite. For this I store name, email address, role, a hash of the password (not the password itself) and the date of the last sign-in. The data is kept in a locked file on the server at STRATO, not in a database and not with third parties.

Invitation: On request, I send you a link by email that lets you set your password. The link is valid for 7 days and can only be used once.

Cookie: Only in the internal area does signing in set a technically necessary session cookie. It ends when you sign out, after 30 minutes of inactivity or after 8 hours at the latest.

Protection against misuse: After several failed attempts, sign-in is blocked for 15 minutes. For this I briefly store only irreversible check values of the email address and IP address, which expire after 15 minutes.

Legal basis and duration: Art. 6(1)(b) GDPR (providing access). I delete your account as soon as you wish or access is no longer needed.

5. No cookies, no tracking, no external services

This website sets no cookies and uses no audience measurement technologies. No advertising or social media services, no embedded videos or maps and no fonts or scripts from third parties are loaded. The site search and all calculators work locally in your browser. The only exception is the session cookie in the internal area (see section 4).

Settings you trigger yourself: Using the "Aa" switch in the header you can choose the colour scheme (light, dark, automatic), the font size and offline use. Only when you change a setting does your browser store it locally on your device (local storage, entries "rv-theme", "rv-fs", "rv-offline" and, if you pause motion in graphics, "rv-motion"). If you turn on "Remember progress in checks and menu on this device", your browser also stores the ticked items in checks and learning paths and the last opened menu section (entries "rv-save", "rv-chk-…" and "rv-menu"). These entries are deleted when you turn it off. These values are not sent to the server and only serve to restore your choice on your next visit. You can delete them at any time in your browser settings or by resetting the switch. The legal basis is Section 25(2) no. 2 TDDDG, because you expressly want to use the service this way, and Art. 6(1)(f) GDPR.

Offline use: If you turn on "Save for offline use", your browser stores pages and files of this website in a local cache (service worker). This only happens at your request. The cache is deleted when you turn it off.

Quizzes, calculators and generators: All input (for example password test, sign, device inventory, deadline calculator) is processed only in your browser. It is neither sent nor stored. Files such as the CSV list are created locally by your browser.

Page feedback: If you tap "Yes" or "No" under "Was this page helpful?", the server increases a counter for this page. Only the page name and the number of answers are stored, no IP address, no time and no cookies. It is not possible to identify you. The "Found a mistake?" link only opens the contact form with a prepared text.

6. External links

This website links to external sites, for example authorities. When you click on them, you leave this website. The respective provider is responsible for data processing on the linked sites.

7. Encrypted transmission

This website is delivered over an encrypted connection (HTTPS). You can recognise this by the padlock symbol in your browser's address bar.

8. Your rights

Under the GDPR you have the right of access (Art. 15), rectification (Art. 16), erasure (Art. 17), restriction of processing (Art. 18), data portability (Art. 20) and to object to processing based on legitimate interests (Art. 21). Please contact the email address above.

You also have the right to lodge a complaint with a data protection supervisory authority. For Hamburg this is the Hamburg Commissioner for Data Protection and Freedom of Information (datenschutz-hamburg.de).

9. Currency

As of November 2026. I update this policy when the website or the legal situation changes.