Effective date: July 26, 2026
The short version
Everything you type into our calculators stays on your device. There are no accounts, no forms, and no servers receiving your grades.
What we don’t collect
We do not collect, transmit, or store your grades, targets, category names, or any other calculator input. All calculations run entirely in your browser using JavaScript delivered with the page.
What stays on your device
To make return visits useful, calculator inputs are saved in your browser’s localStorage — a small store that lives only on your device and is never sent to us. Clearing your browser’s site data removes it completely.
If you use a copy link button, your current inputs are encoded into that link’s address so the person you share it with sees the same numbers. Share those links deliberately; the data travels in the link itself, not through any server of ours.
Hosting logs
This site is served by a hosting provider (Cloudflare Pages), which — like essentially all web hosts — may keep standard, short-lived technical logs (such as IP addresses and requested URLs) to run and secure the service. We do not use these logs to identify visitors.
Analytics
We run a self-hosted, cookie-free analytics tool (Umami) on our own domain to count page views and see which calculators get used. It sets no cookies, collects no personal information, and cannot see anything you type into a calculator. The data stays on our own server and is never shared or sold.
Advertising
The site currently shows no advertising. If ads are introduced in the future, they will be clearly labeled, they will never sit between a calculator’s inputs and its results, and this policy will be updated first with the ad provider named. Ad scripts cannot read what you type into the calculators.
Children’s privacy
Our tools are usable by students of all ages precisely because they collect nothing: no accounts, no personal information, no tracking profiles.
Changes and contact
Material changes to this policy will appear on this page with an updated effective date. Questions? Contact us at [email protected].