Privacy Policy
Last updated: July 4, 2026
12 Rooms (12rooms.app) is a reference site for Zi Wei Dou Shu and BaZi with free in-browser calculators, an optional AI reading, and a paid PDF report. Birth data is intimate, identifying information; this page describes exactly what we do — and don't do — with it.
The free calculators run in your browser
When you calculate a Zi Wei chart or a BaZi chart, the computation happens entirely on your device. Your birth date, hour, and gender are not sent to our servers to produce the chart.
After you calculate a chart, the page's address (URL) includes your birth date, hour, and gender so the chart can be bookmarked and shared. Anyone you share that link with can see those details, and analytics tools (see below) may record the URL. If you don't want that, don't share the link.
The AI reading sends chart structure to a server
The optional "Generate my reading" feature sends a summary of your computed chart (the palace and star structure, plus the birth details it was computed from — never your name; we don't ask for one) to our server, which forwards it to Anthropic's Claude API to generate the text. Generated readings are cached on our infrastructure (Upstash Redis), keyed by the chart structure, so repeat requests for the same chart don't re-generate. Your IP address is used for rate limiting.
The paid report goes through Gumroad
The PDF report is sold via Gumroad (gumroad.com), a third-party checkout operated under its own privacy policy. Payment details are handled by Gumroad; we never see your card number. The birth details you enter at checkout are sent to us with your order and are used solely to prepare your report, which is delivered to your email address. We do not use them for marketing, and we do not sell or share them with anyone. To have your order data deleted, reply to your Gumroad receipt.
Analytics
We use Google Analytics 4 to understand aggregate site usage (pages visited, country, referrer). GA4 sets cookies and may record page URLs, which for shared chart links include the birth parameters described above. We use this data only in aggregate and do not attempt to identify individual visitors.
What we don't do
No advertising networks, no selling of data, no accounts, and no data collection beyond what is described on this page.
Contact
For anything related to a purchase, reply to your Gumroad receipt — it reaches us directly. For everything else, message us via Substack (dvdmaru.substack.com).