Legal

Privacy Policy

Last updated: March 2026 · Effective immediately

TL;DR — The short version

Data Mirror collects absolutely nothing about you. All analysis happens locally in your browser. No data is ever sent to our servers — we don't even have a server that collects user data. Everything stays on your device, always.

1. Who we are

Data Mirror (datamirror.eu) is a browser extension and website created to help users understand where their data goes when they browse the web — and what it's worth on the advertising market. The extension is developed independently and is not affiliated with any advertising network, data broker, or tracking company.

2. What data we collect

We collect no data whatsoever.

The Data Mirror extension operates entirely on your device. Specifically:

All network request analysis happens locally in your browser's service worker
Your browsing history, visited URLs, and detected trackers are stored only in your browser's local storage (chrome.storage.local)
No data is transmitted to any external server controlled by Data Mirror
We have no backend, no database, no analytics, no telemetry
We never see your browsing data — it never leaves your device

How it works technically: When you visit a website, the extension intercepts outgoing network requests and compares them against a local database of 1,000+ known trackers, Big Tech domains, and data resellers. This comparison happens entirely within Chrome's extension sandbox — no external call is needed for the classification itself.

3. Third-party services used by the extension

The extension makes a single type of external request: geographic lookups via ip-api.com (HTTPS) for domains not already in our local database. This request contains only a domain name (e.g. example.com) — never any personal information, your IP address, or browsing context.

Over 95% of domains are resolved locally without any external call. ip-api.com is used as a last resort for unknown domains only. Please refer to ip-api.com's privacy policy for details on their data handling.

4. Data stored on your device

The extension stores the following data locally on your device only:

Domain history — the last 30 sites you visited, with their privacy scores and detected trackers. Automatically limited to 30 days.
Session data — aggregated stats per day (number of requests, trackers detected, score range). No full URLs or personal data.
UI preferences — your preferred block order in the extension popup, stored in localStorage.

You can delete all locally stored data at any time from the Export tab in the extension, or by uninstalling the extension entirely.

5. This website (datamirror.eu)

This website is hosted on Cloudflare Pages (United States). Cloudflare may collect standard server logs (IP addresses, request timestamps) as part of their infrastructure operations. Please refer to Cloudflare's privacy policy for details.

We do not use any analytics tools, tracking pixels, cookies, or advertising on this website. No user data is collected by datamirror.eu itself.

6. Your rights under GDPR

Since we collect no personal data, most GDPR provisions do not apply in a traditional sense. However:

Right of access — all data related to you is stored locally on your device and is directly accessible to you at any time
Right to erasure — you can delete all local data at any time from within the extension, or by uninstalling it
Right to portability — you can export all your local data as CSV or JSON from the Export tab in the extension

7. Children's privacy

Data Mirror does not knowingly collect any information from children under 13. Since we collect no data from any user, this applies universally.

8. Contact

Questions about this privacy policy? Contact us at hello@datamirror.eu.

9. Changes to this policy

If we ever update this policy, the new version will be posted on this page with an updated date. Given the nature of the extension (zero data collection), significant changes are unlikely. We will never introduce data collection without clearly informing users in advance.