Free Pregnancy Due Date Calculator

Estimate a pregnancy due date and gestational age from the first day of the last menstrual period.

Pregnancy Due Date Calculator

Enter a value to begin.

How to use this pregnancy due date calculator

  1. Enter the first day of the last menstrual period and the date on which to estimate gestational age.
  2. Check the inputs and preview, then use the primary action.
  3. Download, copy or use the result shown by the tool.

How the result is calculated

The conventional estimated due date is 280 days after the first day of the last menstrual period. This assumes reliable menstrual dating; ACOG says first-trimester ultrasound is the most accurate way to establish or confirm gestational age.

Method source: ACOG guidance on estimating a due date.

All calculation and transformation work happens in this browser tab. No entered value is sent to an Noler Tools application server.

Important limitations

Results are provided for convenience and should be checked independently before an important decision. A format or checksum result never authenticates an identity, document, account, licence, vehicle or registration.

Health limitation: This is a general educational estimate, not medical advice, diagnosis or a substitute for care from a qualified clinician. Do not use it to make treatment, nutrition, pregnancy or emergency-care decisions.

Frequently asked questions

Is this pregnancy due date calculator free?

Yes. It is free to use and does not require an account.

Does Noler Tools save my input?

No. The input and result remain in temporary browser memory and are not uploaded or saved by this site.

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