Privacy notice

What happens to the numbers entered

The figures entered into the form are sent to the server once per calculation, processed transiently in memory to compute the result, and returned. They are never stored: there is no database, no user accounts, and request contents are not written to logs. Error traces exclude all amounts.

Share links

The “Copy link” feature encodes the entered figures into the page URL so a result can be reproduced. The site does not deliberately store these URLs, but like any web address they live in browser history, may appear in the hosting provider's routine access logs when opened, and are visible to anyone the link is shared with.

Analytics and cookies

The site uses Vercel Analytics, a privacy-friendly, cookieless analytics service, to count page views and feature usage. Events carry event names only — never the figures entered or the results computed. Because the site sets no cookies and uses no equivalent tracking technologies, no consent banner is required under the UK Privacy and Electronic Communications Regulations (PECR).

The site stores one small preference in your browser's local storage: whether the opening notice has been seen (and, if chosen, to keep it hidden for a week). It is strictly functional, set only by your own action, and never sent to the server.

Contact

Privacy questions reach the operator via the contact email on the terms of use page.