This English version is provided for convenience; the Vietnamese version prevails in case of discrepancy.

Personal Data Protection Policy

Last updated: November 2026

This policy describes how this website processes personal data, in line with Vietnam’s Decree No. 13/2023/ND-CP on personal data protection. Our principle: collect as little as possible, never sell it, and never share it for advertising.

1. Data we process

• Birth details (optional name, date and time of birth, gender, place of birth): used to calculate your chart directly in your browser. Your chart history is stored only in your browser’s storage (localStorage) on your device and is not sent to our server.
• When searching for your city of birth (countries other than Vietnam / China): the text you type and the country code are sent to our server to look up the place list; the server does not store this text in association with any user. The chart is still calculated in your browser.
• When looking up dataset readings: your browser sends only a lookup key in the form “year-month-day-hour-gender” (no name or place of birth). The server does not store this key in association with any user.
• When using AI readings / Compatibility: the structure of your chart (chart date, stars, palaces — your name is not sent) and your question are sent to our server and forwarded to a third-party AI model provider to generate a response. Our server does not store conversation content; storage on the AI provider’s side is governed by that provider’s policies.
• Technical logs: your IP address is held temporarily in memory to rate-limit AI requests (automatically deleted after 1 hour) and may appear in server logs kept for operations and security.

2. Purposes and legal basis

Data is processed only to provide the features you actively request (creating a chart, looking up readings, asking the AI). Entering your information and clicking to create a chart or send a question is treated as consent for the corresponding purpose. Date and time of birth are not sensitive personal data under Decree 13/2023, but we still keep processing to a minimum.

3. Your rights

• Delete your chart history at any time by clearing this website’s data in your browser.
• Do not use the AI features if you do not want your chart data sent to an AI provider.
• Request information, withdraw consent or lodge a complaint about data processing via the contact details below.

4. Cookies, browser storage and tracking

This website uses a single functional cookie. It does not use advertising cookies, analytics cookies or third-party tracking tools:

• NEXT_LOCALE — remembers the language you chose (vi or en) so the site opens in that language next time. It is set only when you choose a language or open an English page (/en); it lasts 1 year; it contains no personal data and is not used to identify or track you.

The site also keeps a few settings in your browser storage (localStorage) on your device, which are not sent to our server: light/dark theme, chart calculation school settings, the country of birth you last chose, and your chart history (see section 1).

This cookie and data are necessary for the features you choose; you can delete them at any time in your browser’s site data settings (the site will then return to Vietnamese and default settings).

Fonts are loaded from Google Fonts, so your browser connects to Google’s servers when you open a page.

5. Contact

Please send any personal data requests via the Issues section of the project’s source code repository.