Pregnancy Due Date Calculator
Estimated due date from your last period, using Naegele's rule.
How to use it
- Pick the first day of your last menstrual period.
- Read the estimated due date.
- See how many weeks along the estimate puts you today.
About this tool
This estimates a due date with Naegele's rule, the first day of your last menstrual period plus 280 days, and shows how far along that puts you today. It assumes a regular 28 day cycle, so it is only an estimate, and only about 1 in 20 births happen on the due date. This is not medical advice. Your healthcare provider can confirm dating with an ultrasound scan.
Examples
Last period started January 1Due about October 8Last period 10 weeks agoAround 10 weeks gestational age todayCommon uses
- Estimate a due date from your last period
- See your current week of pregnancy
- Plan around an approximate date
- Have a date before a dating scan
FAQ
Is my date uploaded?
How is the date worked out?
Is this medical advice?
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