The short version
The dates you type into a DateTimeHQ calculator are processed entirely on your own device. They are never sent to our server, stored in a database, or attached to your identity in any way. Closing the tab or refreshing the page clears everything you entered.
Analytics
We use Google Analytics to see aggregate information such as which calculator pages are visited and roughly how many people use the site each day. This tells us which tools are worth improving next. Google Analytics sets cookies in your browser to tell one visit from another. We set it up to record only the page you are on, never the dates, ages, or other values you type into a calculator or that appear in a page link, and we don't use it to build a profile of any individual visitor. If you would rather not be counted, Google offers a browser add-on to opt out.
Advertising
DateTimeHQ may display a small number of ads to help cover hosting costs. If we use a third-party ad network, that network may set its own cookies and use browsing data to show more relevant ads, in line with its own privacy policy. Where this applies, you can usually control ad personalization through your ad settings with that provider, or by adjusting your browser's cookie and tracking preferences.
Cookies
The calculators themselves don't set any cookies. They don't need to, since nothing is saved between visits. Any cookies present on the site come from Google Analytics or advertising, as described above, and you can block or clear them at any time through your browser's settings without affecting how the calculators work.
Links you enter into a calculator
Some calculators reflect the values you enter into the page's URL (for example, so you can bookmark or share a specific date range). This happens entirely in your browser and doesn't involve our server, but if you copy and share that URL with someone else, the dates in it will be visible to them.
Children's privacy
DateTimeHQ is a general-audience reference tool and isn't directed at children. We don't knowingly collect personal information from anyone, regardless of age, since the calculators don't ask for or store personal information in the first place.
Changes to this policy
If this policy changes in a meaningful way, we'll update the date at the top of this page. Continued use of the site after a change means you accept the updated policy.
Questions
If you have a question about this policy or how the site handles data, get in touch through the contact page.