The calculators run in your browser. The measurements you type are not sent to us.
Your shopping list is saved in your browser's local storage on your own device. It's not sent to us, and you can clear it at any time from the list page.
We use Google Analytics to count page visits and how often each calculator is used. It doesn't receive your measurements. We have turned off Google's advertising features, and Analytics doesn't load at all if your browser sends a Global Privacy Control or Do Not Track signal.