Due Date Compass

Due Date Compass is a set of free pregnancy date calculators. Enter one date (a last period, a conception date, an IVF or IUI transfer, an ultrasound or a due date you already have) and it shows the estimated due date, how far along you are today and the key dates in between, from the second trimester to the weeks around the due date.

There are ten calculators: due date, weeks pregnant, a week-by-week pregnancy calendar, conception date, IVF due date, ovulation, implantation and pregnancy test timing, pregnancy weight gain, corrected age, and a maternity leave planner with each U.S. state's paid leave rules. Each one shows the math it used and names its sources, such as the dating conventions of the American College of Obstetricians and Gynecologists. They need no account and run in the browser; the dates entered are not sent anywhere or saved.

Plain-English guides explain how due dates are calculated and why they change. The site gives general information, not medical advice: the date that counts for care is the one a doctor or midwife sets.