Short version: what you type into a calculator stays in your browser. The site keeps your email address only if you give it, and counts pageviews only in aggregate.
What's collected
- Your email address, if you sign up. It is stored by the email service, Buttondown, and used only to send the occasional email about a new calculator or a rule change that affects one. You confirm the address before anything is sent, and every email has an unsubscribe link.
- Pageview counts, in aggregate. Cloudflare Web Analytics counts which pages are viewed, the site that linked to them, and broad browser, device, and country information. It uses no cookies and builds no profile of you.
What isn't
- Anything you type into a calculator. The math runs in your browser. Inputs are not sent to a server, stored, or logged, and they are not written into the page address while you type.
- Unless you share a link. "Share this scenario" builds a link that carries your inputs in its address. Anyone you send it to can read them, and, like any web address, it reaches the site's host when someone opens it.
- No tracking cookies, ads, or session recording. Nothing about you is sold or handed to anyone else.
Fonts
Pages load their typefaces from Google Fonts, so your browser fetches them from Google, which sees your IP address the way any web server does.
Questions
Write to hello@taxweasel.com.
Updated November 6, 2026