Privacy

The short version: your ZIP code stays on your device, and there are no accounts.

Last updated: 2026-11-02

Your ZIP code

The calendar is computed in your browser. When you enter a ZIP code, your browser downloads one small data file named after the ZIP's first three digits (for example, the file for 554 covers every ZIP from 55400 to 55499). The full ZIP code is not sent to our server.

What is stored on your device

Your last ZIP code, so you can reuse it (browser local storage, key last-zip).
Your light or dark theme choice, if you make one (key theme).

You can clear both by clearing this site's data in your browser. The calculator keeps its numbers in the page address so you can share them; nothing is saved elsewhere.

Server logs

Like any website, our server receives the standard information your browser sends with each request, such as your IP address, the page requested and your browser type. We use it to keep the site running and secure.

Analytics

This site does not currently run analytics. We do not use advertising or tracking cookies. If that changes, this page will say so before it happens, and you will be asked for consent where the law requires it.

Contact

Questions about privacy: [CONTACT EMAIL].