Privacy Policy

Last updated 2026-09-15.

What we collect

• Analytics. We use Google Analytics 4 to understand which pages are useful. It collects information such as pages viewed, approximate location, device type and referring site, using cookies.
• Email sign-ups. If you request a setup list, your email address and the page you signed up on are stored in a Google Forms spreadsheet so we can send it to you.
• Messages. If you use the contact or partner form, your name, email and message are delivered to us by email through FormSubmit.
• Calculators. Calculators run in your browser. The numbers you enter are not sent to us.

Affiliate links and cookies

When you click an Amazon link, Amazon may set cookies to attribute a purchase to us. Amazon's own privacy notice governs what happens on Amazon.

Your choices

You can block or delete cookies in your browser, use the Google Analytics opt-out browser add-on, and unsubscribe from any email we send. To ask us to delete an email address, use the contact form.

Children

This site is intended for adults and does not knowingly collect information from children under 13.

Changes

We will update this page if our practices change.