Privacy Policy

Effective from: October 8, 2026

This site is operated by Quiet Hours Studio (Serbia). For any question about this policy or your data, contact support@instacalc.co.

This policy explains what information Lull (available at instacalc.co/, "we," "us," or "the site") collects, how it's used, and the choices you have. If you have questions, reach us at support@instacalc.co. See also our Terms of Service.

Information we collect

Lull's calculators run entirely in your browser. What you enter (times, ages, hours slept, drinks, time zones and the other inputs on each tool) is worked out on your device and is not sent anywhere when you calculate. The site keeps only your choice of 12- or 24-hour clock in your browser's local storage, plus, on our own devices, a marker described under “Analytics”. We don't require an account, and we don't collect names, email addresses, or other personal details through the calculators.

Each tool can make a share link. If you copy one, the inputs of that tool are written into the link's address, so anyone you send it to can see them. Opening such a link requests that address from our web host, like any page request, so the inputs can appear in the host's access log. As soon as the page has read them, it removes them from the address bar, before the Google Analytics and Google AdSense scripts load, so neither analytics nor advertising receives them.

We do collect standard technical information automatically, such as browser type, device type, pages visited and an approximate location, through the analytics and advertising tools described below.

Cookies and similar technologies

This site uses cookies and similar technologies to keep the site working properly, understand how it's used, and serve advertising. Cookies are small text files stored on your device by your browser.

We use Google's consent management to apply regional privacy rules. For visitors in the European Economic Area, the United Kingdom, and Switzerland, advertising and analytics cookies are disabled by default and are not set unless you consent through the consent prompt shown on the site. For visitors in other regions, including the United States, these cookies are used as described in the "Advertising and Google AdSense" and "Analytics" sections below. You can change cookie behaviour at any time through your browser settings, and, where a consent prompt is shown, through that prompt.

Advertising and Google AdSense

We use Google AdSense to display ads on this site. Google is a third-party vendor. Third-party vendors, including Google, use cookies — including the Google advertising cookie (also known as the DoubleClick cookie) and the DoubleClick DART cookie — to serve ads to you based on your prior visits to this site and other sites on the internet. Google and its ad-technology partners (including through Google's ad exchange) use these cookies to serve and measure personalized ads.

You can control the ads Google shows you, and turn off ad personalization, at Google Ads Settings (also reachable at myadcenter.google.com). You can opt out of personalized advertising from many other third-party vendors at www.aboutads.info/choices (US) or youronlinechoices.eu (EU). Blocking or deleting cookies in your browser settings also stops these cookies being used.

Turning off ad personalization, or declining consent where a consent prompt is shown, does not remove ads — non-personalized ads may still be served, since advertising is what pays for this site. More detail on how Google uses cookies in advertising is in Google's Advertising policies.

Analytics

We use Google Analytics 4 to understand aggregate traffic patterns, such as which pages are viewed, how visitors arrive at the site, and how they navigate it. Google Analytics may set cookies to measure this; where regional rules require consent (see "Cookies and similar technologies" above), those cookies are not set unless consent is given. When you press a calculator’s button and get a result for new inputs, the site sends Google Analytics one “calculation completed” event with the name of the tool, never the times or other values you entered. Our own devices carry a marker (local storage, or a cookie named lull_internal) so that our visits are left out of our traffic figures. Analytics data is used in aggregate form and isn't used to identify individual visitors. You can read more about how Google uses data from sites that use its services at Google's Partner Sites policy.

Your choices

Most browsers let you block or delete cookies through their settings.
Where a consent prompt is shown, you can change your advertising and analytics cookie choices there at any time.
You can opt out of personalized Google ads through Google Ads Settings.
You can learn more about how Google uses data from sites that use its services at Google's Partner Sites policy.

Children's privacy

This site is not directed at children under 13, and we do not knowingly collect personal information from children. If you believe a child has provided us with personal information, contact us and we'll take appropriate action.

Third-party links

Our tool and methodology pages link out to external sources, including government health sites, for reference, and every page links to the Lull Android app on Google Play (an Android icon in the header, a row in the phone menu and a Google Play badge in the footer). Each Play link carries only a label for where the link was placed, so we can see which links are used; it carries nothing about you. We aren't responsible for the privacy practices of those third-party sites, and we encourage you to review their policies separately.

Changes to this policy

We may update this policy from time to time. Changes will be posted on this page with a new “Effective from” date.

Contact us

Questions about this policy can be sent to support@instacalc.co.

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