Estimate your due date from your last period or conception date.
Estimates only - not medical advice.
From your last menstrual period we add 280 days (Naegele’s rule), adjusted for your cycle length. From a conception date we add 266 days. We also show how far along you are today.
Find more pregnancy and fertility calculators on the home page.
Most commonly by adding 280 days to the first day of your last period (Naegele’s rule).
It’s an estimate; an early ultrasound gives the most accurate dating.
Enter your average cycle length and we adjust the due date accordingly.
Yes - switch modes and we add 266 days from conception.
No - always confirm dating with your doctor or midwife.