Pregnancy Week Calculator
Determine your current pregnancy week. With development information about the baby.
Note: These calculations are for informational purposes only and do not replace professional tax or financial advice. All information without guarantee.
Frequently Asked Questions
How are pregnancy weeks counted?
Pregnancy weeks (SSW) are counted from the first day of the last menstrual period, not from conception. So at SSW 1-2, you are not actually pregnant yet. Conception typically occurs around SSW 3.
What happens in each trimester?
First trimester (weeks 1-12): organ development. Second trimester (weeks 13-27): growth and movement. Third trimester (weeks 28-40): maturation and preparation for birth.
What is the Pregnancy Week Calculator?
The pregnancy week calculator computes the current week of pregnancy and shows progress with development information.
How does the Pregnancy Week Calculator work?
Enter the first day of the last period. The calculator computes the current pregnancy week, day and remaining days until the due date. Information about the baby's development in each week is provided.
Key Data and Facts
Pregnancy: 40 weeks / 280 days. 1st trimester: weeks 1-12. 2nd trimester: weeks 13-27. 3rd trimester: weeks 28-40. Premature birth: before week 37.
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