Privacy Policy

Last updated: July 10, 2026

Sparkfield is a free, no-signup tool. This page explains what happens to your data when you use this site — in short, very little, because there isn't much to explain.

What we don't collect

There are no accounts and no login. The calculators on this site run entirely in your browser: whatever you type into a calculator (times, weights, dates, and so on) is used to compute a result on your device and is never sent to or stored on our servers.

Analytics

This site may use Cloudflare Web Analytics to understand how many people visit and which pages they read. It's beacon-based and privacy-first by design: no cookies, no cross-site tracking, and no persistent identifier that follows you between visits or between sites. It reports aggregate counts (page views, rough location, device type) — it does not identify you individually, and we don't combine it with anything else.

Third-party links

Some pages link out to outside sources (for example, the medical or veterinary references a calculator cites). Those sites have their own privacy practices, which this policy doesn't cover.

No sale of data

We don't sell, rent, or share visitor data, because we don't collect any in identifiable form to begin with.

Changes to this policy

If what we collect ever changes — for example, if a future feature adds a contact form or email signup — this page will be updated first, with a new "last updated" date above, before that feature ships.

Contact

A dedicated contact address for this site isn't live yet. Check back here once one is — this page will link it the same day.