Privacy Policy

What we collect

When you create an account, we collect your email address and store the projects and calculations you choose to save. Calculator inputs, unit preferences and plans are stored locally in your browser (localStorage) and, if you are signed in, optionally synced to your account. We also collect anonymous usage statistics (see Analytics below).

Analytics

We use Google Analytics 4 to understand how the site is used — for example which calculators and guides are opened, when a plan is created or exported to PDF, and general traffic sources. We do not collect names or other directly identifying details in analytics.

Analytics runs under Google's Consent Mode. Until you accept analytics cookies, Google Analytics operates in a cookieless mode that collects only aggregated, anonymous measurements. If you accept, Google Analytics sets cookies to measure returning visits more accurately. You can accept or decline at any time, and change your choice later via “Cookie settings” in the page footer. Data is processed by Google; see Google's own privacy resources for details, and note that analytics data may be retained for up to 14 months.

Cookies and local storage

MaterialCalc uses browser localStorage to save your calculator settings, unit preferences and projects between sessions, and authentication cookies (via Supabase) when you are signed in. These are strictly necessary for the site to function and are always active.

Analytics cookies are only set if you consent via the cookie banner. We do not use advertising or cross-site tracking cookies.

Legal basis

We process account data to provide the service you request (performance of a contract). Analytics cookies are processed only on the basis of your consent, which you may withdraw at any time without affecting prior processing.

Your rights

You have the right to access, correct or delete your personal data, to object to or restrict processing, to data portability, and to withdraw analytics consent. You can withdraw consent via “Cookie settings” in the footer, delete locally stored data by clearing site data in your browser, and request account deletion by contacting us. If you are in the EU/EEA, you also have the right to lodge a complaint with your local data protection authority.

Third parties

We use Supabase for account authentication and data storage, Google Analytics for usage measurement, and Vercel for hosting. We do not sell your data to third parties.

Contact

For privacy questions or to exercise your rights, contact us via our Contact page.