Privacy

Last updated 10 October 2026

Your drink log

The drinks you log, your bedtime and your half-life setting are saved in your browser's local storage on this device. There is no account, and this site does not upload your log. Clearing your browser data deletes it, and it is not shared between devices or browsers.

Usage analytics

This site uses Google Analytics 4 to count page views, so we can see how the calculator is used. It runs on mycaffeinelevel.com as soon as a page loads, and it does not run on any other origin.

Google Analytics receives a page view with the page address (without any query string or fragment), the page title, the referring site address (also without query strings), and the standard information Google collects with every request, such as your IP address, browser and device type, and approximate location. Google Analytics sets first-party cookies to recognise repeat visits. Google signals, ad storage and ad personalisation are turned off, and ad data is redacted.

Your drink names, caffeine amounts, times, bedtime, half-life setting and anything else in your log are never sent. The site does not track form entries, searches or clicks.

To stop it, block www.googletagmanager.com and *.google-analytics.com in your browser or with an extension. Cookies Google Analytics already set are not deleted by this site; they expire on their own, or you can clear them in your browser settings.

Analytics is not active on this site in this browser, so there is nothing to send.

Hosting

Like any website, the hosting provider receives standard request information, such as your IP address and browser type, when it delivers these pages.

External links

The research notes link to third-party sites. Those sites have their own privacy practices and only receive a request if you open a link.