Privacy Policy

Effective July 9, 2026. This page is maintained by MaterialCalc to explain how MaterialCalc.io handles personal data.

MaterialCalc collects the minimum data needed to run the site: your account email, the projects you choose to save, subscription status from Stripe, and consent-based analytics. We never sell personal data and never see your card number. You can request access or deletion at any time by email. Using the free calculators requires no account at all — see the free material calculators, the terms of service that govern paid plans, and the cookie policy for the tracking detail.

1. Who is responsible for your data?

MaterialCalc.io ("MaterialCalc", "we", "us") is operated by MaterialCalc. For any privacy question, subject-access request, or complaint, contact privacy@materialcalc.io.

2. What data does MaterialCalc collect?

• Account data — when you sign in with Google or email/password we receive your email address, display name, and (for Google) your profile picture URL.
• Saved projects — calculator inputs and results you choose to save to your account.
• Subscription & billing — if you upgrade, Stripe processes your payment. We store only your Stripe customer ID, subscription tier and status; we never see or store card numbers.
• Marketing email — if you opt in to product updates or the newsletter, we store your email address and consent timestamp.
• Usage analytics — with your consent (see Cookies below) we collect anonymised, aggregated page-view data via Google Analytics 4 with IP-anonymisation enabled and advertising signals disabled.
• Server logs — our hosting layer records standard request logs (IP address, user-agent, path, timestamp) for security and abuse prevention. Retained for 30 days.

3. Why do we use your data (legal bases under GDPR)?

• To provide the calculators and your account — performance of contract.
• To process payments and manage subscriptions — performance of contract.
• To send transactional email (approval, receipts, security) — legitimate interests and contract.
• To send marketing email — only with your explicit consent, which you can withdraw any time from the email or by contacting us.
• To measure and improve the site with analytics — only with your consent given via the cookie banner.
• To keep the service secure — legitimate interests.

4. Which cookies and tracking do we use?

We use a minimum of essential cookies (session, authentication, subscription state, cookie-consent record) that cannot be disabled without breaking the site. Analytics and any future advertising cookies are strictly opt-in and blocked until you accept them in the banner. Full details are on our Cookie Policy page.

5. Who do we share your data with?

• Supabase — authentication, database, file storage (data hosted in the EU where possible).
• Stripe — payment processing (PCI-DSS Level 1).
• Resend — transactional and (opted-in) marketing email delivery.
• Cloudflare — CDN, DDoS protection and edge hosting.
• Google (LLC / Ireland) — Google Analytics 4, only if you consent; Google Sign-In if you use it.
• Lovable — the platform we build and deploy the app on.

We do not sell your personal data and we do not "share" it for cross-context behavioural advertising as defined by the CCPA/CPRA. Where subprocessors are located outside the EEA/UK, transfers rely on the European Commission's Standard Contractual Clauses and/or the EU-US Data Privacy Framework.

6. How long do we keep your data?

• Account and saved projects — for the life of your account. Delete your account any time from Settings; we permanently erase your data within 30 days.
• Billing records — retained for 7 years to comply with tax law.
• Server logs — 30 days.
• Marketing consent records — until you unsubscribe, plus 3 years as proof of consent.

7. What are your rights?

Depending on where you live, you may have the right to:

• Access the personal data we hold about you.
• Correct inaccurate data.
• Delete your data ("right to be forgotten").
• Restrict or object to processing.
• Data portability (receive your data in a machine-readable format).
• Withdraw consent at any time (analytics and marketing).
• Lodge a complaint with your local data-protection authority.
• (California residents) Opt out of "sale" or "sharing" of personal information — we do neither, but you may confirm this via email.

Email privacy@materialcalc.io to exercise any of these rights. We respond within 30 days.

8. Can children use MaterialCalc?

MaterialCalc is not directed to children under 16. We do not knowingly collect data from children. If you believe a child has provided data, contact us and we will delete it.

9. How do we keep your data secure?

Data is transmitted over HTTPS/TLS 1.2+, stored in encrypted databases with row-level security, and access is restricted to authenticated staff on a need-to-know basis. Passwords, where applicable, are hashed with bcrypt via our authentication provider.

10. How will you hear about changes to this policy?

We will post material changes on this page and update the effective date at the top. Substantial changes to how we use your data will be notified by email.

What else should I read?

• Terms of Service — the contract that covers Pro subscriptions, refunds and estimate accuracy.
• Cookie Policy — every cookie we set, why, and how long it lives.
• About MaterialCalc — who builds the calculators and how the formulas are verified.

If you upgrade, billing terms live in the Pro pricing page, and the material guides in the materials library work without any account or tracking.

11. How do you contact us about privacy?

Privacy questions: privacy@materialcalc.io
Legal notices: legal@materialcalc.io
General support: support@materialcalc.io