Calculator

Pregnancy-week calculator

See which pregnancy week you are in today from the last period or an estimated due date.

Enter either the first day of the last period or an estimated due date. The tool shows today as weeks + days.

Calculate

Enter the details and press Calculate. The result will appear here.

Fill in only one reference if the two dates disagree; clinical dating comes first.
The count is not a diagnosis.

Week + days — what does that mean?

Clinical gestational age is often written as completed weeks plus extra days, for example 16 weeks + 3 days.

Can I use the due date instead of the last period?

Yes. If your clinician gave a due date, that field can be used as the reference.

Week counting follows the same 40-week clinical frame. It does not replace ultrasound dating.