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Pregnancy Due Date Calculator

Estimate your due date and current pregnancy week from your last period.

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Only used with last period.
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How the due date is estimated

The most common method, Naegele's rule, adds 280 days (40 weeks) to the first day of your last menstrual period (LMP), assuming a 28-day cycle. If you know your conception date, the due date is roughly 266 days later. We adjust for cycle length when you calculate from your last period.

For information only — always confirm dates with your healthcare provider.