How Many Weeks Pregnant Am I? Due Date & Prenatal Schedule
From your last period or conception date: your current week, trimester, and the 12, 16, 20, 28, and 36-week appointment dates
Pick whichever date you know — the first day of your last period or your conception (ovulation) date — and Naegele's rule (LMP + 280 days) gives you the due date, how many weeks along you are today, your trimester, and the days remaining. A timeline lays out where each trimester starts and ends, and a table maps the appointments that actually go in the calendar: the 12-week NT scan, the 16-week quad test, the 20-week anatomy scan, the 28-week glucose test, and weekly checkups from 36 weeks, with dates already past marked as such. It's for planning the schedule before you're sitting in the clinic. All calculations run inside your browser, so the dates you enter are never sent to a server.
🔒 Everything runs 100% in your browser. Your files and input are never uploaded to any server.
How to use
- Choose the tab for the date you want to calculate from: last menstrual period (LMP) or conception (ovulation) date.
- Select that date in the date field.
- Your due date, gestational age, trimester, and days remaining appear automatically.
- Review the trimester timeline and key prenatal checkups at weeks 12, 16, 20, 28, and 36, and copy the results if you need them.
FAQ
- How is the due date calculated?
- It follows Naegele's rule, adding 280 days (40 weeks) to the first day of your last menstrual period. If you enter a conception date instead, it converts that to an LMP equivalent by adding the typical 14 days to ovulation.
- How far off can it be from the actual birth date?
- This is an estimate — actual delivery commonly falls within about two weeks on either side of the due date. Confirm your dating with an ultrasound at your OB-GYN.
- Are the dates I enter saved on a server?
- No. Everything is processed in your browser, and no date information is ever transmitted or stored.