What happens on your device
All calculations (fasting windows, schedules, the timer, statistics) run in your browser. Your fasting sessions and preferences are stored locally using your browser's storage (localStorage and IndexedDB). No account exists, and nothing you enter into the calculators, planner, or timer is transmitted to us or anyone else.
What leaves your device
- Standard web requests: your browser fetches this site's pages, styles, scripts, and the Archivo font from Google Fonts. Font requests are subject to Google's privacy policy.
- Share links you create contain only a fast duration and a clock time: no history, no identity. Sending a link is your choice.
- Calendar (.ics) files and JSON/CSV exports are generated locally and saved to your device; we never see them.
Analytics and cookies
This site currently uses no analytics and sets no tracking cookies. If aggregate, privacy-conscious analytics are ever added, this page will describe exactly what is collected first, and personal fasting data will not be part of it.
Deleting your data
The history pagehas a "Delete all data" control that permanently removes locally stored sessions. Clearing your browser's site data does the same. Because we hold nothing, there is nothing for us to delete on any server.
Contact
Questions about this policy can be sent to the site operator. This page was last updated in August 2026 and will be revised if any practice described here changes.