Due Date Calculator

Estimate your baby’s due date and related pregnancy dates.

Last Menstrual Period (LMP) Date Conception Date IVF Transfer Date

Start Date of Last Period (LMP)

Average Cycle Length (days)

Conception Date

IVF Transfer Date

Embryo Age

Your Estimated Pregnancy Dates

Estimated Due Date (EDD)

—-

Current Gestational Age

— weeks — days

Estimated Conception Date

—-

Understanding Your Due Date:

The due date is an estimate of when your baby will be born. While the average pregnancy lasts about 40 weeks, only a small percentage of babies are born exactly on their due date.

Last Menstrual Period (LMP) Method: This is the most common method. It assumes pregnancy lasts 280 days (40 weeks) from the first day of your last period. Conception is estimated to occur around 14 days after your LMP.

Conception Date Method: If you know your exact conception date (e.g., from ovulation tracking), this method adds 266 days (38 weeks) to that date to estimate your due date.

IVF Transfer Method: This method is used for pregnancies resulting from In Vitro Fertilization. The due date is calculated by adding a specific number of days to your embryo transfer date, depending on the embryo’s age.

3-day embryo transfer: Add 263 days to transfer date.
5-day embryo transfer: Add 261 days to transfer date.

These calculations provide valuable estimates. However, for the most accurate dating and personalized information, always consult with your healthcare provider, especially as early ultrasound scans can provide a more precise due date.

Discovering your pregnancy is an exciting moment, followed by one big question: when will my baby arrive? Our Due Date Calculator provides a personalized estimate of your baby’s birth date based on key dates from your cycle or treatment. Only about 5% of babies are born exactly on their due date, so use this as a helpful guide for your pregnancy journey.

Track your healthy progress with our Pregnancy Weight Gain Calculator.

How to Use the Due Date Calculator

Our calculator is designed for simplicity and accuracy. Follow these steps to get your results:

Choose Your Calculation Method:
- Select the method that applies to you: Last Menstrual Period (LMP), Conception Date, or IVF Transfer Date.
Enter the Required Date:
- For LMP: Enter the first day of your last menstrual period
- For Conception: Enter the known date of conception
- For IVF: Select your embryo type and enter the transfer date
Click ‘Calculate’:
- Instantly receive your estimated due date (EDD), current gestational age, and key pregnancy milestone.

How Due Dates Are Calculated

Pregnancy dating follows a standardized medical timeline. The most common method, Naegele’s Rule, calculates your due date as 40 weeks (280 days) from the first day of your Last Menstrual Period (LMP).

Common Due Date Calculation Methods

Method	Calculation	Note
Last Menstrual Period	LMP + 280 days	Standard method for most pregnancies
Conception Date	Conception + 266 days	Less common; requires knowing exact date
IVF Transfer Date	Transfer date + 261 days	For 5-day blastocyst transfers

What If My Cycles Are Irregular?

If your menstrual cycles are irregular or you’re unsure of your LMP, an early ultrasound (usually at 8-12 weeks) is the most accurate way to determine your due date. This scan measures the Crown-Rump Length (CRL) of the embryo.

Learn more with our Crown-Rump Length Calculator.

Understanding Your Results

Your results will include:

Estimated Due Date (EDD)
Gestational Age (current weeks/days)
Trimester Breakdown
Key Milestones for prenatal appointments

Pregnancy Timeline by Trimester

Trimester	Weeks	Key Developments
First	1-13	Positive test, first ultrasound
Second	14-27	Feeling baby move, anatomy scan
Third	28-40+	Final growth, preparation for delivery

Why Your Due Date Matters

Your due date helps healthcare providers:

Monitor your baby’s growth
Schedule prenatal tests at correct times
Make decisions about care after due date

Preparing for Your New Arrival

Knowing your due date helps you plan:

Learn: “What to Expect When You’re Expecting” provides excellent guidance
Plan: Schedule maternity leave
Register: Create a registry with Amazon Baby Registry

Calculate future costs with our Birth Control Cost Calculator.