Privacy policy

Information you provide

An account holds your email address, managed by our sign-in provider. Signing up is optional — predictions work without one.

To make and save predictions you may enter: a child's name, sex, date of birth or age, height and weight measurements, and optionally their ethnicity; and the parents' heights and optionally weights. Predictions generated from these inputs are saved to your account alongside them.

Guest mode

Without an account, predictions run without being saved to any profile, and we never ask for a name or date of birth. The service can be configured to record anonymized prediction inputs and results for model improvement — never names, account references, IP addresses, or device identifiers. This recording is switched off unless we say otherwise here.

How information is used

To compute predictions, show your history, and run your account. Nothing else: no advertising, no sale of data, no sharing for marketing.

Services that process data on our behalf

Like most apps, we run on infrastructure operated by others, each receiving only what its job needs:

• Clerk — sign-in and account management (your email address).
• Supabase — the database holding profiles and saved predictions.
• Vercel — hosting for the app and its API.
• Google Cloud — runs the ML growth model; it receives measurements only, never names or account details.
• OpenAI — generates the LLM-based estimates and explanations; it receives measurements, parent heights, and ethnicity where provided, never names or account details.

Children's privacy

The service is for parents and guardians, who enter information about their own children. It is not directed at children, and accounts are for adults. A child's information exists in the service only because an account holder entered it, and the account holder can delete it at any time.

Retention and deletion

Saved data is kept while your account exists. Deleting your account (Account → Delete) permanently removes the account, every child profile, and every saved prediction. This is immediate and cannot be undone.

Security

Data moves over encrypted connections and is held by the providers above under access controls. No system is perfectly secure, which is one more reason we collect little.

Changes

If this policy changes, the date above changes with it. Material changes to what is collected would be announced in the app, not slipped into this page.