Free Pregnancy Tool
Find the due date from the last period, or from how many weeks pregnant you are today. Private - nothing leaves this page.
The first day of the last menstrual period, not the last day.
Use the weeks and days you were told - for example 12 weeks + 3 days.
Please enter a valid date.
A due date calculator estimates when a pregnancy will reach 40 weeks. You can start from the first day of the last period, or from how many weeks pregnant you are today. It uses the same 280-day model as the rest of these tools.
Pregnancy is counted as 280 days from the first day of the last menstrual period. If you enter that date, the due date is 280 days later. If you enter how many weeks and days pregnant you are today, the calculator subtracts that from today to find the start, then adds 280 days.
The due date is the one number everything else hangs off - the current week, scans, travel, and the countdown. Once you have it, you can see the week at a glance instead of asking, and plan around the timeline instead of guessing.
FAQ
How due dates are calculated, and where to go if you already have one.
Add 280 days (40 weeks) to the first day of the last menstrual period (LMP). This is Naegele's rule, the same 280-day model midwives and obstetricians use. A dating scan can still move the due date.
Enter the weeks and days you were told, counted from the last period. The calculator works backwards to find the LMP-equivalent start, then adds 280 days to get the due date.
It uses the standard 280-day pregnancy model. Only about 5% of babies arrive on the exact due date. Use a date confirmed by a midwife or dating scan when you have one. For any clinical decisions, talk to a healthcare provider.
Then you do not need this calculator. Enter that date in the pregnancy week calculator to see the current week, or use date lookup and the milestone timeline to plan ahead.
Enter your due date to instantly see your current week and day, trimester, how far along you are, and what your baby is approximately the size of.
Use tool →Enter your due date and any date to see what pregnancy week, day, and trimester you'll be at. Perfect for planning travel, appointments, and milestones.
Use tool →A surprisingly common problem for partners. How pregnancy weeks are counted, why the system is confusing, and how to always know the answer.
Read article →A clear breakdown of the 40-week pregnancy timeline, from trimesters to key milestones, so partners always know where things stand.
Read article →Built for dads & partners
Stop asking. Stop guessing.
Open the app and you're caught up - week by week, until your baby is here.
$4.99 · One-time · Yours forever