Privacy

Short version: nothing you type leaves your browser.

What happens to an expression you type

The tools run locally in the page. Your input is not submitted to a server, is not added to a URL that is sent anywhere (the address bar copy stays on your machine until you share it), and the last expression is kept in your browser's localStorage so the box is filled in when you come back. Clearing site data removes it.

Cookies and trackers

• No cookies are set.
• No third-party JavaScript, fonts or analytics are loaded — every file comes from this origin.
• No advertising scripts, no social widgets, no cross-site request to any other domain.

Server logs

Like any web server, nginx records the page requested (URL, timestamp, user agent) for operation and abuse handling. That log contains no expression or form data, because the tools do not send any.

Children

The subject matter is school mathematics and the site is deliberately usable by students, which is exactly why there is no account, no tracking and no advertising: there is no personal data to collect.