Pregnancy Due Date Calculator

Calculate your baby's due date instantly based on your last menstrual period. Get accurate delivery date with countdown timer.

Calculate Your Due Date

Enter the first day of your last menstrual period to calculate when your baby is due

First Day of Last Menstrual Period (LMP)

Select the first day of your last menstrual period. This is the standard method used by doctors to calculate due dates.

Key Features

Accurate due date calculation using Naegele's Rule

Countdown timer showing days and weeks remaining

Easy-to-read date format with day of the week

Copy and share your due date results

Calculation history for multiple estimates

How Due Date is Calculated

Naegele's Rule: Add 280 days (40 weeks) to your LMP

LMP Method: Most commonly used by doctors worldwide

Average Cycle: Based on 28-day menstrual cycle

Full Term: 37-42 weeks, with 40 weeks as target

Tips for Accurate Dating

Know Your LMP: Remember the first day of your last period

Regular Cycles: Most accurate for 28-30 day cycles

Early Ultrasound: Consider ultrasound for irregular cycles

Healthcare Provider: Always confirm with your doctor

How to Use the Due Date Calculator

Step-by-Step Instructions

Find Your Last Menstrual Period Date

Locate the first day of your last menstrual period (LMP) - this is the starting date for calculation.

Enter the LMP Date

Input the date using the date picker or type in MM/DD/YYYY format for accurate calculation.

Calculate Due Date

Click calculate to get your estimated due date using Naegele's rule (280 days from LMP).

Review Pregnancy Timeline

See how many weeks and days until your due date, plus current pregnancy progress.

Save Your Results

Copy the due date or generate a PDF with pregnancy timeline for your records.

Plan Prenatal Care

Use the due date to schedule prenatal appointments and prepare for important milestones.

Pro Tips for Accurate Dating

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Track menstrual cycles: Keep a record of your periods for more accurate LMP dating in future pregnancies.

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Regular cycles assumed: Calculation assumes 28-day cycles - irregular cycles may affect accuracy.

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Early ultrasound confirmation: Dating ultrasounds between 6-10 weeks provide the most accurate due dates.

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Full-term range: Normal pregnancies deliver anywhere from 37-42 weeks - due dates are estimates.

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Medical confirmation: Always confirm pregnancy with healthcare providers and schedule prenatal care.

Frequently Asked Questions

How do I calculate my due date?

Add 280 days (40 weeks) to the first day of your last menstrual period (LMP). This is called Naegele's Rule and is the standard method used by doctors worldwide.

When is my due date?

Your due date is 40 weeks (280 days) from the first day of your last menstrual period. Enter your LMP date in our calculator to get your exact due date with countdown timer.

How accurate is the due date calculator?

The due date calculator is accurate to within a few days when based on a regular 28-day cycle. However, only 5% of babies are born on their exact due date, with 90% born within 2 weeks of the calculated date.

What is the difference between due date and delivery date?

Due date and delivery date are often used interchangeably. The due date is an estimate of when your baby will be born, while the actual delivery date is when your baby is actually born.

Can I calculate due date without knowing LMP?

If you don't know your last menstrual period date, you can use conception date (add 266 days) or get an ultrasound for the most accurate dating, especially in early pregnancy (6-12 weeks).

What if I have irregular periods?

If you have irregular periods, the LMP method may be less accurate. Consider getting an early ultrasound or consult your healthcare provider for more precise dating methods.

Important Medical Disclaimer

This due date calculator provides estimates only and should not replace professional medical advice.Due dates are estimates and only about 5% of babies are born on their exact due date. Always consult your healthcare provider for accurate pregnancy dating, monitoring, and medical advice throughout your pregnancy journey.