Privacy policy

What we collect

When you use a calculator

Nothing. Your inputs and results stay in your browser. We do not send them to our servers, store them, or see them, unless you ask us to email your results to you.

If you email yourself your results

Each calculator has an optional “email me these results” form. If you use it, the email address you give and the results summary you chose to send (which reflects the figures you entered) are passed to Resend, the email provider that delivers the message on our behalf. We do not store your results on our own systems. Resend, the email provider that delivers the message, processes and retains sent messages (including their content) for a period governed by its own retention policy.

If you join the updates list

Your email address is added to our updates list only when you tick the optional box on a results email or submit the sign-up form on the homepage. The address is stored with Resend. Before we send any newsletter we will send you a confirmation request, and you can unsubscribe at any time using the link in any email or via the contact form.

If you submit the contact form

Your name, email address, chosen topic, and message are delivered to our inbox via Resend. As part of spam protection, your IP address may be held briefly in a rate-limit cache and your submission checked by our hosting provider's bot-detection service. Both checks run only when you submit the form, set no tracking cookies, and are not used for advertising.

When you visit the site

Our hosting provider records standard server logs: IP address, user agent, request paths, and timestamps. These exist for security, debugging, and performance. We do not tie them to individual identities.

If you accept analytics

We use Google Analytics to count which calculators get used, so we know what to improve. It loads only after you accept analytics on the cookie banner, and not before. If you accept, Google sets analytics cookies and receives usage data (such as pages viewed and rough location) as a data processor on our behalf. If you decline, or ignore the banner, no analytics script loads and no analytics cookie is set. We never enable Google's advertising features, so your data is not used to build ad profiles. You can change your mind any time by clearing this site's data in your browser, which brings the banner back. See the cookie policy for the specific cookies.

What we do not do

• No analytics unless you opt in. Nothing loads until you accept the cookie banner.
• No advertising cookies, tracking pixels, or profiling.
• No sale of personal data, ever.
• No sharing of your data with anyone except the service providers listed below, and only to the extent they need it to deliver their service.

Data stored in your browser

The site stores one item in your browser's localStorage: your choice on the cookie banner (accepted or declined), so we do not ask again on every visit. It stays on your device, is never transmitted to us, and you can clear it at any time through your browser settings, which brings the banner back. The site sets no cookies except where noted in the cookie policy.

Who processes your data

These third parties process data on our behalf:

• Vercel Inc.(United States): hosting, server logs, and the contact form's bot-detection check.
• Resend (United States): delivery of results emails and contact form messages, and storage of the updates list.
• Upstash (United States): operates the short-lived rate-limit cache that briefly holds IP addresses submitted with the contact form.
• Google LLC (United States): Google Analytics usage measurement, only if you accept analytics on the cookie banner.

Your rights

Depending on where you live, data protection laws (such as US state privacy laws and the EU and UK GDPR) may give you the right to access, correct, or delete personal data we hold about you, to object to processing, and to withdraw consent at any time. The personal data we typically hold is an updates-list email address and any contact messages you have sent us. You can remove yourself from the updates list via the unsubscribe link in any email. For anything else, send a message via the contact form and we will act on it.

Data retention

• Updates-list addresses are held until you unsubscribe or ask us to remove you.
• Results emails: we do not store your results on our own systems. Resend, the email provider that delivers the message, processes and retains sent messages (including their content) for a period governed by its own retention policy.
• Contact messages are kept in our inbox for as long as needed to handle your enquiry, then deleted.
• Server logs are retained for a limited period determined by our hosting provider, then deleted.

Children

The site is a general-audience tool for people managing household bills. It is not directed at children under 13 and we do not knowingly collect their data.

Changes to this policy

If how the site handles data changes (for example, if advertising is ever added), this policy will be updated first and the effective date at the top of this page will change.

Contact

Questions or requests: send us a message via the contact form.