Privacy

The short version: we collect nothing. No accounts, no analytics, no ad networks, no cookies of our own.

WHAT STAYS ON YOUR DEVICE

Calculator settings (tank size, blends, prices) are saved in your browser's local storage so they're there next fill-up. They never leave your device; clear your browser data to erase them.
OBD-II readings from the read-from-car feature are processed entirely in your browser and never transmitted anywhere.
Offline copies of the site's files are cached by your browser so the tools work without signal.

Hostinger hosts the site and, like any web server, sees standard request logs (IP address, pages requested).
Google Fonts serves the two typefaces; Google may log those font requests.
The EPA's fueleconomy.gov answers the flex-fuel compatibility lookups — your browser queries it directly with the year/make/model you select, nothing more.
Amazon — some guide links are affiliate links. If you click one, Amazon sets its own cookies to attribute the visit, per Amazon's own privacy policy. As an Amazon Associate, this site earns from qualifying purchases.

The site is open source — you can verify all of the above in the code itself, or open an issue there if something looks off.