Due Date Calculator
Find your estimated due date, how many weeks pregnant you are, your trimester and key dates ahead.
Enter the first day of your last menstrual period (and your usual cycle length) or your conception date. You’ll get an estimated due date, how far along you are, and the dates of common pregnancy milestones.
Estimates for general guidance only — every baby is different. Ask your pediatrician about your own child.
How it works
- From your last period: due date = first day of last period + 280 days (40 weeks), adjusted if your cycle is longer or shorter than 28 days.
- From conception: due date = conception date + 266 days.
- Trimesters: first (weeks 1–13), second (14–27), third (28 to birth).
Your healthcare provider may adjust your due date after an early ultrasound, which is usually the most accurate way to date a pregnancy.
Getting ready
- Baby registry checklist — start around 20–28 weeks.
- Hospital bag checklist — pack by about 36 weeks.
- Nursery setup and safe sleep.