Privacy

No accounts, no tracking

EngiRef has no sign-up, no login and no user profile. It loads no advertising trackers, no third-party analytics SDKs and no tracking pixels, and it sells nothing about you to anyone, because it collects nothing about you to sell. There is no consent banner on this site for the same reason: there is no non-essential tracking to consent to.

• No account is needed to use any part of the app, free or Premium.
• No cookies are set for advertising, profiling or cross-site measurement.
• The compatibility runtime loads only after you activate it yourself.

Your data stays in this browser

EngiRef is a static site. There is no server database and no sync service: your progress, settings, saved formulas, favourites, calculation history and workspace state are written to this browser's localStorage under the scoped keys below, and they never leave the device unless you export them yourself. Clearing your browser storage deletes them permanently, and nobody, including us, holds a copy to restore from.

• web-presence:engiref
• native-practice:engiref
• native-library:engiref
• native-workspace:engiref
• native-settings:engiref
• revenuecat-app-user-id:engiref
• web-locale

Inspecting, exporting and deleting your data

The Data route lets you read every value EngiRef has stored, export it as JSON, import it into another browser, and erase it. It touches only the keys listed above, so unrelated data belonging to other sites on this origin is left alone. Because the data lives on your device, a deletion request is something you carry out yourself in seconds, and no request to us is required.

Payments

Premium is processed by RevenueCat Web Billing and Stripe. Your email address and card details are handled directly by those providers under their own privacy policies - EngiRef never sees, receives or stores card data, and it has no access to the payment method behind a subscription. An anonymous purchase id is kept in this browser so Premium is recognised on this device; keep the receipt email, because it is what proves a purchase and what carries the cancellation link. No RevenueCat key, product id or entitlement secret is part of your stored data.

Analytics and hosting

EngiRef is hosted on Cloudflare Pages and served from Cloudflare's global edge, so the network location closest to you serves the files. Traffic measurement is Cloudflare Web Analytics, which is cookieless and aggregate-only: page-view counts and load-performance figures, with no cookies, no cross-site tracking, no device fingerprinting and no individual profiles. Cloudflare also processes standard request data such as IP address to serve and protect the site, as any web host must. No other analytics vendor is used.

Children and changes to this policy

EngiRef is a study and reference tool for a general audience and is not directed at children under 13, and because it holds no accounts it knowingly collects no personal information from anyone. If this policy changes, the updated date at the top of this page changes with it; material changes will be described here rather than applied quietly.