The short version
We collect as little as possible. Our calculators work without accounts, and we do not sell personal data to anyone. Below is the full detail.
What we collect
- Calculator inputs stay in your browser — they are never sent to our servers or stored.
- Contact form messages (name, email, message) are stored so we can reply, and deleted on request.
- Anonymous page-view counts help us see which pages are popular. We hash IP addresses before storing them and never keep raw IPs.
- Server logs (standard web-server logs) are kept briefly for security and debugging, then rotated away.
Cookies
We use a small number of cookies: a session cookie to keep you logged in (admin only), a cookie to remember your cookie-consent choice, and — only if you accept — advertising cookies described below. You can decline non-essential cookies in the consent banner at any time.
Google AdSense and DoubleClick
We use Google AdSense to show ads that keep this site free. Google may use the DoubleClick cookie to serve interest-based ads based on your visits to this and other sites. You can opt out of personalized advertising at Google Ads Settings and learn more at aboutads.info. Google's use of advertising cookies enables it and its partners to serve ads based on your visit to our site and/or other sites on the Internet.
Affiliate links
Some pages contain affiliate links. If you click one and make a purchase, we may earn a commission at no extra cost to you. Clicks are counted in aggregate; we do not track who clicked what.
California residents (CCPA/CPRA)
If you are a California resident, the California Consumer Privacy Act gives you the right to know what personal information we collect, to request deletion or correction of that information, and to opt out of the "sale" or "sharing" of personal information. We do not sell your personal data. However, when you accept advertising cookies, Google AdSense may use your browsing data to personalize ads — California law can treat this as "sharing."
Do Not Sell or Share My Personal Information: to opt out, click "Decline" in our cookie consent banner (or the Do Not Sell or Share link in the footer), which blocks all advertising cookies and personalized ads. You can re-open the banner at any time from the footer's "Cookie settings" link. We will never discriminate against you for exercising these rights.
To exercise any CCPA right (access, deletion, correction, opt-out), contact us through the contact form and we will respond within 45 days as the law requires.
Your rights
You may request a copy of any personal data we hold about you, ask us to correct it, or ask us to delete it. Contact us through the contact form and we will respond within 30 days.
Changes to this policy
We will update this page if our practices change. The "last updated" date below always reflects the current version.