Privacy Policy
Last updated: August 2026
The Short Version
There are no accounts here and we do not ask who you are. We do keep a record of how the site is used, so that broken calculators get found and fixed. Whatever you type into a calculator is worked out in your browser.
Usage Logging
Activity on the site is logged — which pages get opened, what gets clicked, and recordings of how people move through the site. It exists to catch bugs, show which calculators are worth improving, and decide what to build next. Logging runs on every visit and cannot be switched off from inside the site; browser privacy settings, tracker blockers and private browsing all work here if you would rather not be included. Recordings are deleted automatically after 30 days.
Cookies and Browser Storage
The logging tools set cookies and use local storage so that repeat pages in one sitting count as one visit. The site itself keeps two things on your device and nowhere else: your dismissal of the cookie notice, and a short list of calculators you have used. Clearing your browser storage for this site removes all of it.
What You Type Into a Calculator
Every calculator runs in your browser. Your inputs are not sent to us and no calculation happens on a server. If a tool puts your inputs into the page address, that address forms part of the usage record described above.
The Contact Form
The name, email address and message you submit through the contact form are passed to the site operator so the message can be read and answered. They are used for that and nothing else — no mailing list, no onward sharing.
Who Else Is Involved
The logging, the hosting and the contact relay are run by third-party service providers on our behalf, each under its own terms. Nothing is sold, and nothing is passed to advertising networks.
Your Rights
If you are in the EU, EEA or UK, you may ask what is held about you, ask for it to be deleted, or object to it being kept. Because none of it is tied to a name or an email address, finding your records may need the rough time and pages of your visit. Requests go through the contact form.
Changes
This policy may be updated as the site changes. The date at the top reflects the most recent revision.