Pregnancy Due Date Calculator - Calculate Your Baby's Due Date

Calculate your pregnancy due date and track important milestones based on your last menstrual period or conception date with accurate gestational age tracking

Updated: December 2024 • Free Tool

Pregnancy Due Date Calculator

Select the first day of your last menstrual period

Typical range: 21-35 days (average is 28 days)

Your Due Date Results

Estimated Due Date
Select Date
Current Status
-- weeks, -- days
Conception Date --
First Trimester Ends --
Second Trimester Ends --
Full Term Begins --

What is a Pregnancy Due Date Calculator?

A Pregnancy Due Date Calculator is a medical tool that estimates when your baby will be born based on your last menstrual period (LMP) or conception date. It calculates the expected delivery date using the standard 280-day (40-week) pregnancy duration.

This calculator helps you:

  • Track pregnancy progress - Monitor gestational age and milestones
  • Plan prenatal care - Schedule important appointments and tests
  • Prepare for delivery - Estimate when to expect your baby
  • Monitor trimesters - Understand pregnancy stages and development

How Pregnancy Due Date Calculator Works

The calculation uses Naegele's Rule:

Due Date = LMP + 280 days (40 weeks)

For conception date method:

Due Date = Conception Date + 266 days (38 weeks)

The calculator accounts for average cycle length variations and provides estimated conception date, trimester milestones, and full-term pregnancy range.

Understanding Pregnancy Timeline

Gestational Age

Pregnancy duration measured from the first day of your last menstrual period, typically 40 weeks.

Trimesters

Pregnancy is divided into three trimesters: 1st (0-12 weeks), 2nd (13-27 weeks), 3rd (28-40 weeks).

How to Use This Due Date Calculator

1

Choose Method

Select LMP or conception date calculation method

2

Enter Date

Input your last menstrual period or conception date

3

Set Cycle Length

Adjust average cycle length if different from 28 days

4

Get Results

View due date and pregnancy milestones

Benefits of Tracking Your Due Date

  • •
    Prenatal Planning: Schedule important medical appointments and tests at the right time.
  • •
    Milestone Tracking: Monitor baby's development and pregnancy progress week by week.
  • •
    Birth Preparation: Plan maternity leave, hospital bag, and delivery arrangements.
  • •
    Health Monitoring: Track symptoms and changes throughout each trimester.

Factors That Affect Due Date Accuracy

1. Cycle Regularity

Irregular menstrual cycles can affect LMP-based calculations. Ultrasound dating may be more accurate.

2. Ovulation Timing

Women who ovulate earlier or later than day 14 may have different conception dates than estimated.

3. Individual Variation

Each pregnancy is unique. Only 5% of babies are born on their exact due date.

Pregnancy Due Date Calculator - Free online tool to calculate baby due date from last menstrual period with gestational age tracking
Professional pregnancy due date calculator interface featuring input options for last menstrual period and conception date. Provides accurate due date calculations, gestational age tracking, and pregnancy milestone dates with mobile-responsive design.

Frequently Asked Questions (FAQ)

Q: How accurate is a pregnancy due date calculator?

A: Pregnancy due date calculators are accurate within 1-2 weeks. Only about 5% of babies are born on their exact due date, with most births occurring within 2 weeks before or after the calculated date.

Q: What information do I need to calculate my due date?

A: You need either the first day of your last menstrual period (LMP) or your conception date. The LMP method is most commonly used and considered the standard for medical calculations.

Q: Can I use this calculator if I have irregular periods?

A: If you have irregular periods, the LMP method may be less accurate. In such cases, an ultrasound dating scan performed by your healthcare provider will give more precise results.

Q: When should I see a healthcare provider during pregnancy?

A: Schedule your first prenatal appointment as soon as you confirm pregnancy, ideally between 6-8 weeks. Regular prenatal care is essential for monitoring both mother and baby's health throughout pregnancy.