Your privacy
Pregnancy dates are sensitive. The short version: what you enter is calculated in your browser and never sent to us.
Sources last checked . How we write and check
What happens when you calculate
The calculator runs entirely in your browser. The dates and numbers you enter are not sent to our servers or anyone else, are not stored in cookies, local storage or a database, and disappear when you close or reload the page. There are no accounts.
Share links
“Copy link” creates an address ending in something like #edd=2027-06-14&m=lmp&v=1. It contains only your estimated due date, the method name and our calculation version. It never contains your period, conception, transfer or scan dates. The part after # isn’t sent to our server when the link is opened. But anyone you share the link with can read your due date, and it may stay in browser history or synced devices, so share it only with people you trust.
Calendar downloads
“Add to calendar” builds an .ics file on your device and downloads it. We never see it. Once you import it, your calendar provider’s privacy policy applies, and calendar sync may copy it to other devices or accounts.
Analytics, ads and cookies
We don’t use analytics, advertising, tracking pixels, session recording or cookies. Fonts and images are served from our own domain, so opening a page makes no requests to third parties. If we add analytics in the future, it will not record anything you enter in the calculator, and we will update this page first.
Hosting logs
The site is hosted on Cloudflare. Like any web host, Cloudflare processes technical request data, such as IP address, browser type and the page requested, to deliver the site and protect it from abuse. These requests never include your calculator inputs. Cloudflare’s handling of this data is described in its own privacy policy.
Links to other sites
Source links go to the organizations that published them, such as ACOG, the NHS and journals. Their privacy policies apply once you leave this site.
Contact
Variable Ratio publishes this site. For privacy questions, email hello@pregnancyduedatecalculator.com.