About Pregnancy Due Date & Conception Calculator (Naegele’s Rule)
Track your pregnancy timeline. Calculates estimated delivery due date (EDD) using clinical Naegele’s Rule from your last menstrual period (LMP) or conception date, providing current gestational age, trimester tracking, and fetal size milestones.
Key Capabilities & Features
- Estimated Delivery Date calculation via Naegele’s Rule (40 weeks)
- Gestational age in weeks and days with progress percentage
- Trimester breakdown (1st, 2nd, and 3rd trimesters)
- Fetal development size comparison milestones
How to Use Pregnancy Due Date & Conception Calculator (Naegele’s Rule)
Select Method
Choose Last Menstrual Period (LMP) or Conception Date.
Enter Date
Pick the relevant date from the calendar.
View Milestones
Inspect your estimated due date, gestational age, and fetal development size.
Privacy & In-Browser Execution Guarantee
Personal health and pregnancy dates are stored only in your local browser.
Frequently Asked Questions
How does Naegele’s Rule calculate your estimated delivery date (EDD)?
Naegele’s Rule calculates your due date by taking the first day of your Last Menstrual Period (LMP), adding 1 year, subtracting 3 months, and adding 7 days (approximately 280 days or 40 completed weeks).
Can I calculate my due date using my exact conception date or IVF transfer date?
Yes. You can switch the calculation method to conception date (adding 266 days) or in vitro fertilization (IVF) 3-day or 5-day embryo transfer dates for exact gestational age tracking.
What percentage of babies are born exactly on their estimated due date?
Only about 4% to 5% of babies arrive on their exact calculated due date. Most healthy deliveries occur within a 2-week window before or after the 40-week milestone (between weeks 38 and 42).