Privacy Policy

Last updated: 23 May 2026

The protection of your personal data is important to us. In this Privacy Policy, we inform you in accordance with the EU General Data Protection Regulation (GDPR) about the type, scope and purpose of the processing of personal data on the website calcsi.com (hereinafter 'CalcSI' or 'this website'). CalcSI is a free collection of online tools (hash generators, converters, map tools, etc.). We follow a privacy-friendly approach: wherever technically possible, calculations are performed directly in your browser without your input being transmitted to our server.

1. Data Controller

The controller within the meaning of the GDPR and other national data protection laws of the EU member states as well as other data protection provisions is the operator of this website. The full contact details of the controller can be found in the Imprint. For data-protection-related questions you can contact us at any time by email at [email protected].

2. Data Collection When Visiting the Website (Server Log Files)

Every time this website is accessed, our hosting provider or CDN (Cloudflare) automatically collects information that your browser transmits to the server. The following data is collected in particular:

  • anonymised IP address (the last octet is truncated)
  • date and time of access
  • name and URL of the file accessed
  • website from which the access was made (referrer)
  • browser used and, if applicable, the operating system of your device as well as the name of your access provider
  • HTTP status code and amount of data transferred
This data is processed exclusively to ensure a smooth connection, to enable convenient use of the website, to evaluate system security and stability, and to defend against attacks. The legal basis is Art. 6(1)(f) GDPR (legitimate interest in error-free and secure operation of the website). This data is not merged with other data sources.

3. Calculations Within the Tools (Client-Side)

CalcSI privacy highlight: Practically all calculations in our tools (e.g. hash generation, JWT decoding, BMI calculation, unit conversion, colour conversion, etc.) take place entirely in your browser. Your inputs — text, numbers, files, passwords — are at no time transmitted to our server, stored there, or analysed. The JavaScript logic loads after the page is opened and all processing occurs locally on your device. We therefore cannot see what specific values you enter into the tools. Any exceptions are, if at all present, clearly indicated at the individual tool (e.g. when a tool requires an external API).

4. Cloudflare (CDN and DDoS Protection)

This website uses the content delivery network (CDN) and DDoS protection of Cloudflare, Inc. (101 Townsend St, San Francisco, CA 94107, USA). Cloudflare routes all traffic between your browser and our server and in doing so processes your IP address, request headers, geographic region (country level) and technical connection data. This is necessary to accelerate the delivery of the website, to defend against attacks (e.g. DDoS, bot traffic, SQL-injection attempts) and to ensure availability. Cloudflare may set a technically necessary security cookie (e.g. __cf_bm) that expires after a short time. The legal basis is Art. 6(1)(f) GDPR. A data processing agreement (DPA) has been concluded with Cloudflare; transfers of data to the USA take place on the basis of EU Standard Contractual Clauses and, where applicable, the EU-US Data Privacy Framework. You can find further information in the Cloudflare Privacy Policy.

5. Google AdSense

This website uses Google AdSense, an advertising integration service provided by Google Ireland Limited (Gordon House, Barrow Street, Dublin 4, Ireland; parent company: Google LLC, 1600 Amphitheatre Parkway, Mountain View, CA 94043, USA). AdSense uses cookies and comparable technologies (e.g. advertising IDs, web beacons) to deliver ads, measure their delivery and — if consent has been given — show personalised advertising based on your interests. Personal data such as your IP address, device and browser information, approximate location, pages visited and click/interaction data are processed. These may be transferred to servers in the USA and stored there.

The legal basis for personalised advertising is your consent pursuant to Art. 6(1)(a) GDPR, which you can grant or refuse via our consent banner (compliant with TCF v2.2 of the IAB Transparency & Consent Framework). If you refuse consent or withdraw it, we operate AdSense in non-personalised mode (NPA); in this mode ads are served without profile building, but technically necessary data (e.g. IP) is still transmitted. You can deactivate personalised advertising at any time at adssettings.google.com. Transfers of data to the USA are safeguarded by EU Standard Contractual Clauses and the EU-US Data Privacy Framework. More information: policies.google.com/privacy and policies.google.com/technologies/ads.

6. Google Fonts

We embed the Inter font via the Google Fonts webfont service (Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland; as well as Google LLC, USA) from fonts.googleapis.com and fonts.gstatic.com. We want to be explicitly transparent here: when a page is loaded, your browser establishes a connection to Google's servers, in the course of which your IP address, user agent and referrer are transmitted and may be briefly stored in logs. In its judgment of 20 January 2022 (Case 3 O 17493/20), the Munich Regional Court ruled that embedding Google Fonts without consent can violate the right to informational self-determination.

Legal basis: we rely on our legitimate interest in a consistent, fast-loading appearance (Art. 6(1)(f) GDPR). We are working on hosting Google Fonts locally in the future in order to avoid data transmission. More information can be found in the Google Privacy Policy.

7. External Libraries via CDNs (jsDelivr, cdnjs, unpkg)

For the presentation and functioning of the website we embed various JavaScript libraries (including Bootstrap, jQuery, Vue 3, toastr.js, Bootstrap Icons) and associated CSS files via external CDNs, in particular:

  • cdn.jsdelivr.net — jsDelivr (operated by ProspectOne / Volentio JSD Limited)
  • cdnjs.cloudflare.com — Cloudflare CDN for open-source libraries
  • unpkg.com — npm package CDN (Cloudflare)
When loading the website, your browser makes direct connections to these servers, transmitting your IP address, user agent and referrer information. The providers may briefly store this data in server logs in order to provide the service and to defend against abuse (e.g. bot detection). The legal basis is Art. 6(1)(f) GDPR (legitimate interest in a high-performance website with mature open-source libraries). We are evaluating whether to host these libraries locally in the future as well.

8. Cookies and Local Storage

Our own cookies: CalcSI itself does not set any tracking or marketing cookies. Only technically necessary values may be stored in your browser's local storage (e.g. the language last chosen, selected tool settings, your consent status for AdSense). These data remain exclusively in your browser and are not transmitted to our server.

Third-party cookies: Cookies may be set by embedded third-party services, in particular:

  • Cloudflare — technically necessary security cookie (__cf_bm, bot protection)
  • Google AdSense — only after consent; advertising and frequency-capping cookies
You can delete cookies in your browser at any time or prevent them from being set via your browser settings; if all cookies are blocked, the website's functionality may be impaired. You can withdraw or adjust your consent for AdSense at any time via the 'Cookie settings' link in the footer.

9. Map Tools (OpenStreetMap, Overpass API, Geolocation)

Some of our tools (e.g. Lifesaver Map, E-Mobility Map) display interactive maps. The following external services are used for this:

  • OpenStreetMap map tiles: The map data and tiles are provided by the OpenStreetMap Foundation (St John's Innovation Centre, Cowley Road, Cambridge CB4 0WS, United Kingdom) or a mirror server (e.g. tile.openstreetmap.org). When the map is displayed, your IP address, the user agent and request details are transmitted to the tile server. Privacy policy: osmfoundation.org/wiki/Privacy_Policy
  • Overpass API: For points-of-interest searches (e.g. AEDs, charging stations) we use the Overpass API (overpass-api.de, operated by Roland Olbricht). In this process, request parameters and your IP are transmitted to the server. No inputs beyond the search itself are transmitted.
  • Browser geolocation: If a tool uses your location (e.g. 'near me' search), the browser explicitly asks for your permission (Geolocation API). Your coordinates remain exclusively in your browser; they are neither transmitted to our server nor to third parties — unless you actively start an Overpass search in which a geographic bounding-box filter is part of the request.
Legal basis: Art. 6(1)(f) GDPR (legitimate interest in map functionality) and (a) (your consent via the browser geolocation prompt).

10. Hosting

The contents of our website are hosted with the following provider: [PLEASE COMPLETE: hosting provider name and full address]. The hosting provider processes the server log files described in section 2 on our behalf (Art. 28 GDPR). A data processing agreement (DPA) has been concluded with the provider. Legal basis: Art. 6(1)(f) GDPR.

11. Storage Period

We store personal data only as long as is necessary for the purposes described in this privacy policy or as prescribed by statutory retention periods.

  • Server log files: automatically deleted after 14 days, unless security-relevant incidents (e.g. suspected attacks) justify longer storage.
  • Cloudflare security data: according to Cloudflare's retention periods (short, typically a few days to weeks).
  • AdSense data: according to Google's retention periods, see the Google Privacy Policy.
  • Data in local storage: remains in your browser until you delete it or clear your browser cache.

12. Your Rights as a Data Subject

As a data subject, you have the following rights under the GDPR in particular:

  • Right to information (Art. 15 GDPR) — you may request information as to whether and which personal data we process about you.
  • Right to rectification (Art. 16 GDPR) — you may request the correction of inaccurate data or the completion of incomplete data.
  • Right to erasure (Art. 17 GDPR, 'right to be forgotten') — you may request the deletion of your data, provided that no statutory retention obligations stand in the way.
  • Right to restriction of processing (Art. 18 GDPR).
  • Right to data portability (Art. 20 GDPR) — receipt of your data in a structured, commonly used, machine-readable format.
  • Right to object (Art. 21 GDPR) — you may object to the processing of your data on grounds relating to your particular situation.
  • Right to withdraw consent (Art. 7(3) GDPR) — with effect for the future, without affecting the lawfulness of processing already carried out.
  • Right to lodge a complaint (Art. 77 GDPR) with a data protection supervisory authority, in particular in the member state of your habitual residence, place of work or place of the alleged infringement.

An informal email to [email protected] is sufficient to exercise your rights. We will deal with your request promptly and may ask you for identity verification to ensure that the request actually originates from you.

13. Changes to This Privacy Policy

We reserve the right to amend this Privacy Policy so that it always complies with the current legal requirements or in order to implement changes to our services, e.g. when introducing new services. The version available at the time of your visit to the website applies. In the event of material changes, we will additionally inform you in an appropriate form on the website (e.g. via a notification banner).

14. Contact for Data Protection Inquiries

For questions, requests for information, withdrawals or other data-protection-related matters, you can contact us at any time:

Email: [email protected]
Postal address: see Imprint

This privacy policy was created with care. Should anything nevertheless remain unclear, we welcome your feedback at [email protected].