Privacy policy

Last updated: October 21, 2026

Who we are

This site is operated by [to be provided] (owner / legal entity), [to be provided] (country). Contact: [to be provided] (contact email).

What you enter stays on your device

The calculators run in your browser. Times, ages, caffeine amounts and hours of sleep you type are not sent to us or to anyone else.

• Your calculator settings (12- or 24-hour clock, time to fall asleep, cycle length) are saved in your browser’s local storage under “cyclerest:prefs:v1”.
• Sleep debt entries (hours slept on 7 nights and your sleep need) are saved under “cyclerest:debt:v1” so they are there next time. “Clear saved entries” on the sleep debt calculator deletes them.
• Your light/dark theme choice is saved under “cyclerest:theme”.

Nothing else is stored. You can also delete everything by clearing this site’s data in your browser settings. The caffeine and age calculators don’t save anything.

What the server receives

Like any website, the hosting server receives standard technical request data (such as IP address, browser type and the page requested) when you load a page. Server log handling by our hosting provider: [to be provided].

Analytics

We use Google Tag Manager and Google Analytics 4 (GA4), both services of Google, to count visits and see which pages are used. Google Tag Manager loads on every page and runs on every visit; it loads Google Analytics, which sets its own cookies (such as _ga and _ga_WFP64VJ916) and sends Google information such as the pages you view, your browser and device, and your IP address, which Google uses to estimate your general location.

No health information is sent to analytics. The site does not pass anything you type (times, hours of sleep, ages, caffeine amounts) to Google Tag Manager or Google Analytics, and calculator results never appear in page addresses. You can block these cookies in your browser settings or with Google’s opt-out add-on: tools.google.com/dlpage/gaoptout. How Google uses data from sites that use its services: policies.google.com/technologies/partner-sites. Analytics data retention setting: [to be provided].

Cookies and similar storage

We use local storage for your settings, sleep debt entries and theme, as described above. These are needed for the features to work and are not used for tracking. Google Analytics sets its own cookies on every visit (see Analytics). There are no advertising cookies.

Advertising (future)

We plan to show ads on some pages, never between a calculator’s inputs and its results. Ad vendors: [to be provided]. There is no advertising on the site today; this policy will be updated before any is added.

Children

This site is for a general audience, including parents looking up children’s sleep needs. It is not directed at children.

Your rights

We don’t collect what you type into the calculators, so there is nothing for us to access, correct or delete on our side. For questions about server logs, analytics or this policy, contact [to be provided] (contact email). Applicable data-protection law: [to be provided].

Changes

We will update this page when anything changes and show the date at the top.