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Result will appear here.

How to Use

  1. Enter the first day of the last menstrual period.
  2. Select Calculate.
  3. Discuss the estimate with a healthcare professional.

Formula

Example

A period beginning on January 1 produces an estimated due date around October 8 using 280 days.

FAQ

Is the due date exact?

No. Pregnancy length varies and clinical dating may adjust the estimate.

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