How we handle your information

Information we collect

When the legacy input contract is active, the free calculator uses the birth date and optional birth time you enter to create an instant BaZi snapshot in your browser. When the Full BaZi v3 input contract is active, the browser shows a neutral preparation state and does not calculate or display that legacy snapshot as a v3 result.

If you request the full reading, our serverless function receives your email address, birth date, optional birth time, selected Da Yun calculation convention, optional product-update choice, a submission identifier, and the security-check token. A Full BaZi v3 request also includes the IANA birth timezone and, only when the server identifies an ambiguous local time, the earlier or later occurrence you select. The application processes the raw birth details, timezone, fold choice, calculation convention, and security token only for that request to calculate the canonical reading. It does not persist or log those raw fields, send them to analytics, or send them to the email provider.

The server creates a structured, versioned snapshot containing derived information such as the Day Master, visible Wu Xing distribution, Da Yun timing, derived civil presentation, and curated reading content. This snapshot is personal data and may allow temporal information, including an approximate birth year, to be inferred, even though it does not contain the raw birth date, time, IANA timezone, fold choice, or calculation convention.

We retain a minimal lead record containing the email address, consent state, report version, provider message identifier, delivery state, submission time, and source. Our hosting and security systems also process limited technical information, such as network address and request metadata, to deliver the site, prevent abuse, and keep the service reliable.

We record basic usage events, such as a page view, calculator submission, or reading request and its categorical delivery status, to understand whether this smoke test is useful. We do not include email or birth details in analytics, use advertising cookies, or sell personal information.

How we use information

We use the information to generate the legacy browser-based snapshot when applicable, calculate and deliver the reading you request, retry delayed delivery, measure interest in Yun Chapter, protect the form from automated abuse, enforce request limits, and operate the site securely.

The requested reading is a transactional email. We use your email for occasional Yun Chapter product updates only if you select the separate optional checkbox, and you can unsubscribe from those updates at any time.

Service providers

We use a small set of providers that process information only to support this website:

• Vercel hosts the site and serverless form, and Vercel Blob privately stores minimal lead, delivery, and pending-reading records. It also stores a private cleanup marker with a submission identifier and expiry date, but no email, raw birth details, IANA timezone, fold choice, calculation convention, or reading content.
• Resend sends the requested transactional email. Resend receives the recipient address and rendered reading, but not the raw birth date, birth time, IANA timezone, fold choice, or calculation convention.
• Cloudflare Turnstile checks whether a form submission is likely to come from a person rather than an automated system.
• Upstash stores short-lived rate-limit data based on a pseudonymous identifier derived from the network address and limited coordination data for pending-delivery retries. It does not receive raw birth details.
• GoatCounter provides simple, cookie-free traffic and event analytics.

These providers may process data in countries other than your own under their respective security and privacy commitments.

Retention

A derived reading snapshot is deleted after the email provider accepts the message or, in normal operation, within 30 days if delivery remains pending. Pending snapshots become eligible for cleanup after 28 days so the daily process has time to meet that window. The minimal lead, consent, report version, provider message identifier, and delivery state use a 90-day retention window. Automated cleanup starts before the window ends and runs daily so routine timing does not extend that period.

If hosting, storage, or scheduled cleanup is temporarily unavailable, cleanup resumes on the next successful run. An email-provider outage may delay delivery but does not stop the independent cleanup schedule. Rate-limit records are short-lived. Resend retains sent-message and delivery data for 30 days under the current plan. Other infrastructure, security, and analytics providers may retain limited technical records under their documented retention schedules.

Security

We use encryption in transit, private lead storage, restricted service credentials, automated deletion, abuse controls, and pseudonymous rate-limit identifiers. No online service can guarantee absolute security, but we limit collection and access in proportion to this smoke test.

Your rights and choices

Depending on where you live, you may ask to access, correct, or delete your personal information, object to or restrict certain processing, or withdraw consent for future product updates. Every optional product-update email will include unsubscribe instructions. The one-time requested reading is transactional and does not enroll you in updates unless you select the optional checkbox. We may need to verify your request before acting on it.

Contact

For a privacy question or request, email privacy@yunchapter.com.