Pregnancy due date calculator

A Pregnancy Due Date Calculator helps estimate your baby’s expected delivery date based on your last menstrual period or conception date. It provides a quick and easy way to track pregnancy progress and important milestones.

NOTE : we don't collect, process, or store any of the data that you enter while using this tool. All calculation are done exclusively in your locally, and we don't have access to the results. All data will be permanently erased after leaving or close the screen.

How to Calculate Your Baby’s Due Date Accurately

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Published 17 March 2026 | Written by Dr Eva R. Dixon

Understanding your baby’s due date is one of the most important parts of pregnancy planning. While no method can predict the exact day your baby will arrive, accurate estimation helps you track development, plan medical visits, and prepare for delivery with confidence.


📅 What Is a Due Date?

Your due date is the estimated day your baby is expected to be born. A full-term pregnancy typically lasts about 40 weeks (280 days) starting from the first day of your last menstrual period (LMP).

However, it’s important to note that this is only an estimate—not a guarantee.

🧮 Method 1: Calculate Using Last Menstrual Period (LMP)

This is the most commonly used method by doctors.

Steps:

  • Identify the first day of your last menstrual period
  • Add 280 days (40 weeks) to that date

👉 Example:
If your LMP was March 1, your due date would be around December 6.

Best for: Women with regular menstrual cycles (28–30 days)

🧬 Method 2: Based on Conception Date

If you know when conception occurred:

Steps:

  • Add 266 days (38 weeks) to the conception date

This method can be more precise but requires accurate tracking of ovulation or fertility timing.