Privacy policy

Last updated: July 2026.

The short version

ChronoAge Pro is a static website with no accounts and no server-side processing. Every calculation happens locally in your browser. The dates of birth, test dates and caseload labels you enter are never sent to us or anyone else — they stay on your device. Because student dates of birth are sensitive, this is architectural: there is no network path for that data to leave.

What we store on your device

Caseload rows and your light/dark theme choice are kept in your browser'slocal storage so they are there next time. This never leaves your browser, we cannot read it, and you can clear it any time through your browser settings.

Analytics

ChronoAge Pro uses Google Analytics 4 (GA4) to understand which pages are useful — how many people visit each calculator, roughly where in the world they are (country/region), and what device and browser they use. This measurespage visits only, and analytics runs on the live site only, not on development or preview URLs.

It is completely separate from the calculator. The dates of birth, test dates and caseload labels you enter are never sent to Google or to us — GA4 receives no part of them. GA4 sets its own first-party cookies to count returning visits; you can block or clear them through your browser or an ad-/tracker-blocker, and if we ever add advertising we will ask for consent through a banner (see below) before any advertising cookies are set.

Advertising

ChronoAge Pro currently shows no ads. If advertising (such as Google AdSense) is added in future, those services may set their own cookies; we will update this page and — where required, for example for visitors in the EEA and UK — ask for your consent through a banner before those cookies are set.

Your data stays on your device

The calculators are entirely client-side: there is no database of students, no email list you are added to without asking, and nothing for us to sell. This is a deliberate design choice, not a promise we have to police.

Contact

Questions about privacy? Reach us via the contact page.