Privacy

Short version: this site cannot see your dates, because they never leave your device.

What runs where

OvulationCalc is a static website. The calculators are JavaScript programs delivered with the page; when you enter a period date or cycle length, the computation happens in your browser's memory on your own machine. There is no account system, no database, no form submission and no server endpoint that receives your inputs. Reloading the page discards everything you typed; nothing is written to cookies or local storage by the calculators.

What any website visit still involves

Like any site, our hosting provider (Cloudflare Pages) processes standard technical logs — IP address, browser type, the page requested — to serve the pages and protect against abuse. Those logs identify a visit, not the dates you entered into a calculator, which are never transmitted. We do not embed third-party advertising, social-media trackers or external fonts and scripts; the pages load no resources from other companies' servers.

Health information

Because nothing you enter is sent anywhere, there is no health data for us to store, sell, share or lose. If that ever changes — for example if an optional saved-history feature is added — this page will be updated first and the feature will be opt-in, stored on your device unless clearly stated otherwise.

Contact

Questions about this policy can be raised via the contact details on the about page. This policy was last updated in October 2026.

Please read: OvulationCalc is an estimation tool based on calendar averages. It is not medical advice, it cannot confirm that ovulation has happened, and it must not be used as a contraception method — calendar estimates are not reliable birth control. Cycles vary from month to month. If you are trying to conceive, have irregular cycles, or have any health concern, talk to a doctor or midwife.