The short version
Last updated: 25 October 2026.
This site sets no tracking, analytics or advertising cookies. The one thing stored in your browser is a note in local storage recording that you have dismissed the cookie message. That is currently the whole list.
What cookies and local storage are
A cookie is a small text file that your browser stores for a website and sends back on later visits — that is how websites remember things between pages, such as a basket or a sign-in. Local storage is a similar space in your browser, except that what is kept there stays on your device and is not sent back on each visit.
What this site stores today
One item. When you press Accept on the cookie message, the site stores a note in your browser's local storage — its name is prc-cookie-ok — so the message does not reappear on every visit. It holds no name, no address and nothing about your calculations.
Nothing else is stored. Your calculator figures are not saved: they are worked out in the page and gone when you close it, unless you press Share Link, which puts the figures into the web address itself. The site runs no analytics and shows no advertising, so no third party sets cookies through it. Server logs (see the Privacy Policy) sit on the server, not in your browser.
If advertising or analytics are added
This may change. If we introduce advertising — through Google AdSense, for example — or analytics, those services would set cookies of their own: to personalise adverts, or to count visits in a way that recognises a returning browser. They would be set by the provider, not by us, and covered by the provider's policy too.
Before anything like that goes live, this page and the Privacy Policy will be updated, and the cookie message will set out your choices, including how to refuse or opt out. We will not add tracking first and explain it afterwards.
How to clear or block them
You control your browser's storage on every site. Every major browser lets you view and delete cookies and site data, and block them, from its privacy settings — usually under a heading like “Privacy and security”.
Blocking or clearing everything will not break this site. The calculators do not depend on either; the only difference is the cookie message returning, because the note recording your dismissal has been wiped. If anything on this page is unclear, write to [email protected].