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Pregnancy Due Date Calculator

Estimate your due date from your last menstrual period (Naegele’s rule).

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Estimated due date
2024-10-07

Estimate via Naegele’s rule (LMP + 280 days). Consult your doctor.

How it works

Enter the first day of your last menstrual period to estimate your due date.

Frequently asked questions

How is the due date estimated?
Naegele’s rule: 280 days (40 weeks) from the first day of your last period.
Is this accurate?
It’s an estimate; only about 1 in 20 babies arrive exactly on the due date. Your doctor’s scan dating is more precise.