— Privacy Policy
Last updated: September 18, 2026. This page explains what information this site collects, how it's used, and the choices available to you. No account, login, or registration of any kind is required to use this site.
Calculator History
Each calculator keeps a history of your last 25 calculations using your browser's local storage (localStorage). This data stays on your device only — it is never sent to this site's server or to any third party. It persists until you clear it (via each calculator's "Clear history" button) or clear your browser's site data, and it doesn't carry over to a different browser or device.
Contact Form
The Contact page's form is processed by a third-party form-relay service (Web3Forms), which delivers your name, email, and message directly to this site's email address — this site's own infrastructure never stores or sees the submission. See Web3Forms' privacy policy for how they handle that data in transit.
Donations
The optional donation button on the Contact/Donate page is a Stripe-hosted element embedded directly in the page. If you choose to donate, your payment details, email, and any other information needed to process the transaction are collected and processed by Stripe, not by this site — this site never receives or stores your payment information. See Stripe's privacy policy for how they handle that data. Donations are voluntary and are not payment for any product or service.
Server Logs & Analytics
This site is hosted on Cloudflare, which automatically logs standard technical information for security and operational purposes — IP address, browser/device type, pages visited, and timestamps. This site's operator also reviews aggregate traffic statistics (e.g. total visits, request counts, general geographic region) derived from these logs to understand overall site usage. This data is not linked to any other information you provide on the site and isn't used to identify individual visitors.
Children's Privacy
This site is a general engineering reference and isn't directed at children under 13. It doesn't knowingly collect personal information from children.
Changes to This Policy
This policy may be updated from time to time. The "Last updated" date at the top of this page reflects the most recent revision.
Contact
Questions about this policy can be sent via the Contact page.