Due Date Calculator Pregnancy Week By Week



Calculating the due date during pregnancy is an essential aspect of prenatal care. It helps expectant parents prepare for the arrival of their bundle of joy. In this article, we’ll provide a user-friendly calculator using HTML and JavaScript, ensuring accuracy with a precise formula. Let’s explore how to use this calculator effectively.

How to Use

To use the Due Date Calculator, follow these simple steps:

  1. Input the first day of your last menstrual period (LMP) in the designated text field.
  2. Click the “Calculate” button, and the calculator will determine the expected due date based on the reliable Naegele’s Rule.


The Due Date Calculator employs Naegele’s Rule, a standard method used by healthcare providers. The formula is as follows:

Due Date=LMP+280 days


Suppose the first day of your LMP was January 1, 2024. Using the formula:

Due Date=January 1, 2024+280 days

The calculated due date would be October 7, 2024.


Q: Is Naegele’s Rule always accurate for calculating due dates?

A: Naegele’s Rule is a widely accepted and accurate method, but individual variations may occur. Always consult with your healthcare provider for personalized information.

Q: Can the Due Date Calculator be used for irregular menstrual cycles?

A: While the calculator provides a general estimate, irregular cycles may affect accuracy. Consult with a healthcare professional for precise calculations.

Q: Is it safe to rely solely on the Due Date Calculator for pregnancy planning?

A: The calculator is a helpful tool, but it’s crucial to complement it with professional medical advice for a comprehensive approach to pregnancy planning.


The Due Date Calculator simplifies the process of estimating your baby’s arrival. By utilizing Naegele’s Rule, it provides a reliable estimate based on the first day of your last menstrual period. However, always consult with your healthcare provider for personalized guidance and information.

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