Full term is 39-40 weeks. Early term: 37-38 weeks, Late term: 41 weeks.

Pregnancy Calculator | Due Date & Gestational Age Estimator

📖 How to Use This Pregnancy Calculator

Select your calculation method (LMP, Conception Date, or Known Due Date), enter the date, and get your due date, gestational age, trimester, and days remaining.

🤰 Understanding Pregnancy Calculation

A full-term pregnancy typically lasts about 280 days (40 weeks) from the first day of your LMP (Naegele's Rule). Conception usually occurs around day 14 of a 28-day cycle, so due dates are calculated 40 weeks from LMP but only 38 weeks from conception.

📊 Calculation Methods

LMP Method: Due Date = LMP + 280 days (40 weeks). Most common method.
Conception Date: Due Date = Conception + 266 days (38 weeks).
Due Date: Enter known due date to calculate current gestational age.

📅 Pregnancy Trimesters

First (Weeks 1-12): Morning sickness, fatigue, organ formation.
Second (Weeks 13-26): Energy returns, baby movement felt.
Third (Weeks 27-40): Baby grows rapidly, prepare for delivery.

💡 Important Milestones

Week 6-8: First heartbeat
Week 10-12: Nuchal translucency screening
Week 16-20: Anatomy scan
Week 24-28: Gestational diabetes screening
Week 39-41: Full term

❓ FAQ

❓ How accurate is this calculator? ▼

LMP-based calculations have ±7-10 days accuracy. First-trimester ultrasound is most accurate (±3-5 days). Only 5% of babies are born on exact due date.

❓ What if my cycle is longer than 28 days? ▼

For longer cycles, ovulation occurs later. Add the difference to your due date. Example: 35-day cycle = add 7 days.

❓ When does morning sickness start? ▼

Typically begins around week 6, peaks around week 9, and resolves by weeks 12-14.

❓ When can I feel baby move? ▼

Most women feel first movements (quickening) between 18-22 weeks.

❓ What is full term? ▼

Early term: 37-38 weeks, Full term: 39-40 weeks, Late term: 41 weeks, Post-term: 42+ weeks.