BookTrendr Chrome Extension — Privacy Policy
Last updated: October 30, 2026
Short version: the extension reads public book data on Amazon.com and shows it to you. Everything happens inside your own browser. We collect nothing, store nothing on any server, and share nothing with anyone.
This policy covers the BookTrendr — BSR & Categories on Amazon extension for Google Chrome (the “extension”), published by AI4Writers. It explains what data the extension handles, how, and why.
What the extension does
The extension shows the Amazon Best Sellers Rank (BSR) and category ranks of books on Amazon.com pages: under each book in search results, on Best Seller category lists, on a book’s product page and in the carousels on that page.
What data the extension handles
To do its single job, the extension handles website content from Amazon.com — and only that:
- It reads the Amazon.com page you are viewing to find the books on it (their ASIN product IDs and titles).
- When a book scrolls into view, it requests that book’s public Amazon product page and reads the “Best Sellers Rank” and category ranks from it.
It does not handle any other kind of data. It does not collect, read or store:
- your name, email address or any other personal information
- your Amazon account details, orders, cart, passwords or payment information
- your browsing history or activity on any other website
- your clicks, keystrokes or mouse movements
- your location or IP address
How the data is used
The rank data is used for one purpose only: to display it next to the book on the page you are looking at. It is not used for advertising, profiling, analytics, creditworthiness or lending, or anything else.
Where the data is processed and stored
All processing happens locally, inside your browser. Ranks are kept in temporary memory for the open page, so the same book is not requested twice. That memory is cleared when you close or reload the tab. The extension does not use browser storage, does not keep data between sessions, and has no server or database of its own.
Who the data is shared with
No one. The extension does not send any data to AI4Writers, BookTrendr or any third party. It contains no analytics, tracking or advertising code. We do not sell or transfer user data.
To read a book’s rank, the extension requests that book’s product page directly from amazon.com, from your browser. Amazon receives that request the same way it would if you opened the page yourself, including your existing Amazon session. Amazon’s handling of those requests is covered by Amazon’s Privacy Notice. The extension does not contact any other website.
Links to BookTrendr
The extension’s popup includes a link to the BookTrendr research platform at research.ai4writers.club. Nothing is sent there unless you click the link. If you do, that website’s own privacy policy applies.
Permissions
The extension asks for one permission: access to https://www.amazon.com/*. It needs this to read book ranks from Amazon product pages. It runs on no other websites.
Chrome Web Store User Data Policy
The use of information by this extension adheres to the Chrome Web Store User Data Policy, including the Limited Use requirements.
Changes to this policy
If the way the extension handles data ever changes, we will update this page and its date before the new version is released, and clearly tell you about the change in the extension and its Chrome Web Store listing.
Contact
Questions about this policy or the extension: blog@ai4writers.club