Chrona

Cookie Policy

Last updated: August 17, 2026

This Cookie Policy explains what cookies and similar browser storage technologies Chrona ("the Site") uses, why we use them, and what choices you have. This policy should be read alongside our Privacy Policy.

1. What Are Cookies?

Cookies are small text files placed on your device by a website when you visit it. They are widely used to make websites work more efficiently, remember your preferences, and provide reporting information to site operators and advertisers. Cookies set by the website you are visiting are called "first-party cookies." Cookies set by parties other than the website operator are called "third-party cookies."

In addition to traditional cookies, this Site also uses localStorage — a browser-based storage mechanism that keeps data on your device without an expiry date, until you clear it. We treat localStorage data with the same care as cookies.

2. How We Use Cookies and Local Storage

We use cookies and browser storage for the following purposes:

2.1 Strictly Necessary

These are essential for the Site to function correctly. They cannot be disabled without breaking core features.

  • Cookie consent preference (chrona_cookie_consent, localStorage): Remembers whether you have accepted, declined, or customized cookie preferences so the consent banner does not appear on every page load. Stored locally on your device only — never sent to a server.

2.2 Functional / Performance

These improve your experience by remembering your settings between visits. They can be disabled, but some features may not work correctly.

  • Recent bedtime calculations (chrona_recent_bedtime, localStorage): Stores your last few bedtime/wake-up calculations so they appear in the "Recent" panel on return visits. Stored locally; never transmitted to us.
  • Sleep debt log (chrona_sleep_debt, localStorage): Persists your weekly sleep entries across sessions so you don't need to re-enter them. Stored locally; never transmitted to us.

2.3 Analytics (Google Analytics)

We may use Google Analytics to understand aggregate traffic patterns — which pages are visited most, how long visitors stay, and what countries they come from. Google Analytics uses cookies to measure this data.

  • _ga (cookie, 2 years): Distinguishes unique users.
  • _gid (cookie, 24 hours): Distinguishes users within a 24-hour window.
  • _gat (cookie, 1 minute): Used to throttle request rate.

Analytics cookies are only set if you accept them via the cookie consent banner. You can also opt out globally at tools.google.com/dlpage/gaoptout.

2.4 Advertising (Google AdSense)

This Site may display advertisements served by Google AdSense. Google and its partners may use cookies to serve ads based on your prior visits to this Site or other sites on the internet.

  • IDE (cookie, ~13 months): Used by Google DoubleClick to register and report user actions after viewing or clicking one of the advertiser's ads.
  • test_cookie (cookie, session): Used to check whether the user's browser supports cookies.
  • ANID, NID, DSID (Google cookies, duration varies): Used for ad targeting and measurement based on inferred interests.

Advertising cookies are only set if you accept them via the cookie consent banner. You can review or adjust your Google ad personalization settings at adssettings.google.com.

3. Your Cookie Choices

When you first visit the Site, a consent banner appears at the bottom of the screen with the following options:

  • Accept All — enables all cookies, including analytics and advertising.
  • Necessary Only — disables analytics and advertising cookies; strictly necessary localStorage items remain active.
  • Manage Preferences — opens a detailed panel where you can toggle analytics and advertising cookies individually.

Your choice is saved in chrona_cookie_consent (localStorage). You can reset your choice at any time by clearing your browser's site data, or by clicking the button below:

4. How to Control Cookies via Your Browser

You can control or delete cookies at any time through your browser settings. Here are direct links to cookie management instructions for the most common browsers:

Note that disabling all cookies may affect site functionality, especially if you block localStorage.

5. Do Not Track

Some browsers offer a "Do Not Track" (DNT) signal. We currently do not alter our data practices in response to DNT signals, but we will continue to monitor regulatory developments and update this policy accordingly.

6. Changes to This Cookie Policy

We may update this Cookie Policy from time to time. When we do, we will revise the "Last updated" date above. We encourage you to review this page periodically to stay informed about how we use cookies.

7. Contact Us

If you have questions about our use of cookies or this policy, please contact us at [email protected] or via the Contact page.