What are the three pregnancy trimesters?

First trimester: Weeks 1-12. Second trimester: Weeks 13-26. Third trimester: Weeks 27-40.

Due Date Calculator

Calculate your expected due date and track pregnancy stages accurately

💖 Calculate Due Date

Calculation Method:

First Day of Last Menstrual Period:

📊 Results

Milestone	Date

About Due Date Calculator

The Due Date Calculator is an accurate medical tool that helps pregnant women calculate their expected delivery date based on the first day of their last menstrual period or conception date. This calculator uses the famous Naegele's Rule, which is adopted by most doctors worldwide to determine the due date.

Knowing your expected due date is extremely important for both the mother and doctor, as it helps track fetal growth properly, schedule necessary medical checkups, and plan for delivery. The calculator provides detailed information about your current pregnancy week, which trimester you're in, and major milestones throughout your pregnancy.

Our Due Date Calculator offers two calculation methods: the first from the first day of your last menstrual period (LMP), and the second from the conception date. Both methods provide accurate results, but the first method is more commonly used in medical clinics. Remember that the calculated due date is an estimate, as only 5% of women deliver on their exact due date, while 80% deliver within two weeks before or after the expected date.

How to Use the Due Date Calculator

Select the appropriate calculation method (from last menstrual period or conception date)
Enter the first day of your last menstrual period or conception date
Click "Calculate Due Date" button to get results
Review the expected due date, current pregnancy week, and trimester
Check the pregnancy milestones table to know important dates

Frequently Asked Questions

The calculator uses Naegele's Rule: it adds 280 days (40 weeks) to the first day of your last menstrual period. If using conception date, it adds 266 days (38 weeks).

The due date is an estimate. Only 5% of women deliver on their exact due date. About 80% deliver within two weeks before or after the expected date. The date serves as a guide for medical follow-up.

First trimester: Weeks 1-12 (major organs form). Second trimester: Weeks 13-26 (rapid growth). Third trimester: Weeks 27-40 (growth completion and preparation for birth).

It's recommended to visit the doctor as soon as pregnancy is discovered, usually at weeks 6-8. The first visit includes pregnancy confirmation, blood tests, and accurate due date determination using ultrasound.

If your cycle is irregular, it may be difficult to accurately determine the due date. In this case, use the conception date calculation method, or consult your doctor to accurately determine the date using early ultrasound.

Yes, the doctor may adjust the due date based on early ultrasound (especially at weeks 8-13) which provides accurate fetal size measurements and gives a more precise date estimate.

Preterm delivery: before week 37. Full-term delivery: weeks 37-42. Post-term delivery: after week 42. If pregnancy exceeds week 41, the doctor may decide to induce labor.

Usually: monthly until week 28, every two weeks until week 36, weekly until delivery. These schedules may change based on your health and doctor's recommendations.