❤️ Health & Fitness

Pregnancy Due Date Calculator — Calculate Instantly Online

Pregnancy due dates are estimated using Naegele's rule — adding 280 days (40 weeks) to the first day of the last menstrual period. While only about 5% of babies arrive on the exact due date, knowing the estimate helps with prenatal appointments, planning maternity leave and tracking development by week.

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What is Pregnancy Due Date Calculator?

Pregnancy due dates are estimated using Naegele's rule — adding 280 days (40 weeks) to the first day of the last menstrual period. While only about 5% of babies arrive on the exact due date, knowing the estimate helps with prenatal appointments, planning maternity leave and tracking development by week.

Example Calculation

Example: An LMP of 1 January gives an estimated due date around 8 October the same year (280 days later).

Benefits of using the Pregnancy Due Date Calculator

How to Use the Pregnancy Due Date Calculator

  1. Open this page on InstantTool.in
  2. Enter the required values in the input fields
  3. Results update instantly as you type — no submit needed
  4. Adjust inputs to compare scenarios and copy the result

Tips & Best Practices

Frequently Asked Questions

Yes — completely free. No account, email or payment required.
InstantTool uses the same industry-standard formulas as Indian banks and government bodies. Results match what professionals use.
Yes. The layout is fully responsive and tested on popular Indian Android phones and iPhones.
No. All calculations run locally in your browser. InstantTool does not store or share your inputs.
Yes — all 76 tools on InstantTool are free, forever.

Start using the Pregnancy Due Date Calculator now

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Pregnancy Due Date Calculator calculations are a part of daily life for Indian households. A reliable calculator helps avoid errors, supports accurate financial decisions and ensures compliance with the latest Indian standards and tax rules.