Privacy Policy

Calculators run locally

All calculator inputs and results are processed in your browser. They are not sent to or stored on our servers. The values appear in the page URL only so you can copy and share a result link — nothing more.

Accounts (optional)

If you create an account, we store the minimum needed to provide it: your email address, an optional display name, and the results you choose to save. Authentication is handled by Better Auth. If you sign in with Google or GitHub, we receive your basic profile (email and name) from that provider — never your password.

You can delete your account at any time, which removes your saved data.

Analytics

We may use privacy-friendly, aggregate analytics to understand which pages are useful. These measure traffic in aggregate and are not used to build advertising profiles. Analytics are disabled in development.

Cookies

We use only essential cookies: your theme and language preferences, and — if you sign in — your authentication session. No third-party advertising cookies are set.

Your rights and contact

You can access, export or delete your account data. For any privacy request or question, open an issue on the GitHub repository and we will respond.

Children

Metri is not directed at children under 13, and we do not knowingly collect their data.