About OB Wheel

OB Wheel is a free, independent pregnancy-dating tool. It exists to answer one question quickly and clearly: given a date, what’s the estimated due date and how far along is the pregnancy today? It’s built for clinicians who need an answer between patients and for expectant parents checking a date out of curiosity.

What it is — and isn’t

This is an informational calculator, not a medical service. The site is not run by a licensed medical professional, and nothing here should be read as a diagnosis or medical advice. The content is researched and cited against authoritative sources such as ACOG, the NHS, Mayo Clinic and the WHO, and links out to them rather than reproducing their material. If a qualified clinical reviewer is added in future, they’ll be named here — we won’t invent credentials.

How it’s built

The calculator runs entirely in your browser. There are no accounts, no tracking cookies, and no data collection: the dates you type never leave your device. The site is fully static and self-hosts every asset. See Privacy for details and How it’s calculated for the methods.

“OB wheel” is a generic, descriptive term for a pregnancy dating wheel. This site is independent and not affiliated with, or endorsed by, any other product of that name.