How Many Weeks Pregnant Calculator

Work out how many weeks pregnant you are from the first day of your last period or from your due date. For guidance only; not medical advice.

How many weeks pregnant am I?

Pregnancy is usually dated from the first day of your last menstrual period (LMP), not from conception. So "weeks pregnant" is the number of weeks since that date. A full-term pregnancy is about 40 weeks (280 days) from LMP. You can enter either your LMP or your due date; we'll work out how many weeks you are. This is for guidance only; your midwife or doctor will confirm your dates.

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