Privacy
There are no accounts, no sign-up and no stored inputs. The calculator runs entirely in your browser; the numbers you type never reach a server.
The site carries advertising, and the advertising network may set cookies in your browser under its own policy. That is the only third party involved in serving a page.
Server logs exist at the hosting provider in the ordinary way, for delivering pages and blocking abuse. They record the request, not the contents of any field on this site, because no field is ever submitted.
If you clear your browser storage, nothing is lost: this site never wrote any.
Questions about this policy can go to the contact address published on the parent site.