MathTypeXThe MathTypeX editor and its image export run entirely inside your browser. Your equations are not sent to a server, and the site needs no account.
The editor keeps your last equation and a few preferences, such as the open tab, in your browser's local storage so they are there when you return. You can remove them by clearing the site data in your browser.
The pages are hosted on GitHub Pages, which may log standard technical data such as IP addresses when pages are requested, under its own policy. We use Google Analytics to count visits (for example which pages are viewed and from which country); it never receives your equations. We also use Google Search Console to understand how the site appears in search.