Privacy Policy

1. Introduction

This Privacy Policy describes how Thuat Ngu Hanh («we») collects, uses, stores and protects information when you visit the website, create BaZi or Zi Wei charts, use AI analysis, register an account or pay for services.

By using the platform, you confirm that you have read and understood this policy. If you do not agree, please stop using the service. We may update this policy over time; the latest version will be posted on this page with the update date.

2. Data we collect

Chart data: birth date, hour and minute (if provided), gender, timezone, birth place or longitude (if entered), optional display name, and calculation results (Heavenly Stems, Earthly Branches, Five Elements, Zi Wei palaces, major cycles, etc.). Each chart is assigned a system-generated 22-digit key.

Account data: full name, email address, password (hashed, never stored in plain text), approval status, subscription plan, payment history and charts saved to your account.

Service usage: questions sent to AI, generated AI analysis, technical access logs (truncated IP, browser type, access time) for operations, security and system improvement.

Contact information: content you submit via the contact form (name, email, subject, message) when you reach out to us.

3. How we use data

We process data to: calculate and display charts; provide AI readings and chart Q&A according to your plan; manage accounts, subscriptions and payment confirmation; respond to support requests; prevent fraud, abuse and technical attacks.

We do not use chart data for third-party targeted advertising and do not sell or rent customer lists. Internal analytics (error rates, load) use anonymised or aggregated data where possible.

4. Storage and security

Data is stored on servers we operate or on infrastructure providers we select, in regions appropriate to applicable rules. Website connections use HTTPS encryption. Account passwords are one-way hashed; login tokens expire.

We apply reasonable technical and organisational measures: limited internal access, periodic backups, service monitoring. No system is perfectly secure; protect your login credentials and do not share chart keys if you want privacy.

5. AI and automated processing

AI analysis is based on your chart data and questions. Under current configuration, AI requests are processed on internal infrastructure or servers we control — not sent to public AI services unless clearly announced in a future policy update.

AI output is automated and may not be fully accurate. We do not use your questions to train third-party models. Q&A history may be stored linked to chart keys or accounts to enforce plan limits and show results back to you.

6. Cookies and browser sessions

The website uses essential cookies to maintain login sessions, remember language and protect against abuse. We do not run cross-platform ad tracking on core services.

You may clear cookies in browser settings; some features (login, preferences) may not work if cookies are disabled.

7. Third-party sharing

We may share minimal data with: hosting, database and transactional email providers (registration confirmation, password reset); payment gateways when you pay online (subject to their own policies).

We may disclose information when required by law or to protect legitimate interests of users and the system. Chart data is not transferred for partner marketing purposes.

8. Your rights

You may: access account information on the Account page; request email or name corrections via contact; request chart or account deletion (within technical and legal retention limits); withdraw consent by stopping use of the service.

To exercise these rights, contact us via the Contact page with your registered email and a clear description. We respond within a reasonable time, typically within 30 business days.

9. Retention

Guest charts (without login) may be stored per system policy to allow re-access via the 22-digit key. Accounts and saved charts are kept until you request deletion or close your account.

Technical logs and payment records may be kept longer as needed for accounting, disputes or legal compliance, then anonymised or deleted.

10. Children

The service is intended for users aged 16 or older (or the minimum age under local law). We do not knowingly collect data from children. If we learn of a child account without parental consent, we will delete it upon valid notice.

11. Policy changes

We may amend this policy when adding features (e.g. payment gateways, new AI integrations). Material changes will be posted on the website; continued use after the update date means you accept the new version.

12. Contact

For privacy questions or personal data requests, please use the Contact page or the support email published on the homepage. We aim to handle requests transparently and promptly.