Short version: the calculators run entirely in your browser — your measurements are never sent to us. If you create an account, we store your email, your Pro purchase status and the projects, quotes and business details you choose to save, so they're available on all your devices. We don't sell data, show no ads and don't use tracking cookies.
Without an account
Nothing you type into a calculator leaves your device. Your browser's local storage remembers your unit and theme preferences and any projects or quotes you save.
With an account
- Email address — to sign you in (by emailed code) and to match your Pro purchase.
- Saved projects, quotes and business details (including an uploaded logo, tax number and payment details) — synced so you can use them on other devices. Quotes include the client details you enter.
- Purchase status received from our payment provider (plan, status, renewal dates). We never see card details.
- A session cookie (strictly necessary, httpOnly) that keeps you signed in for up to a year.
- If you sign in with Google or Apple: we receive only your account's stable ID and email address, and keep them to recognise you next time. With Apple's “Hide My Email”, we only see the relay address Apple gives us.
Shared quotes
When you share a quote, a copy is stored so your client can open it from the link. Anyone with the link can view it. Your client's acceptance (name and time) is recorded. You can withdraw a shared quote at any time.
Data is stored with Cloudflare (Workers and D1). Sign-in emails are sent through Resend. You can download all your data or delete your account at any time from the account page; deleting your account removes your projects, quotes and business details immediately. Purchase records are kept by our payment provider for legal and tax reasons.
Affiliate links
Some shopping-list items link to retailers such as Amazon with an affiliate tag. If you buy, we may earn a commission at no extra cost to you. The retailer only knows you came from QuantoObra.
Analytics
We may use privacy-friendly, cookie-free analytics (Cloudflare Web Analytics) that count page views without identifying you or tracking you across sites.
Payments
Purchases are processed by Lemon Squeezy as merchant of record, under their own privacy policy. They send us your email and order details so we can activate Pro on your account.
Your rights
You can access, export, correct or delete your data at any time. For anything you can't do from the account page, email support@quantoobra.com.
Last updated: October 27, 2026.