Pregnancy Week Calculator
Determine your current pregnancy week. With development information about the baby. Scientifically based, free, no registration required.
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.
Step-by-Step Guide
How to calculate Ihre aktuelle SSW step by step: 1. Ersten day der letzten Periode enter: Ab diesem day wird die Schwangerschaft gezaehlt, obwohl die Befruchtung erst ca. 2 Wochen spaeter stattfindet. 2. Aktuelle SSW ablesen: Der Rechner calculates die vollendeten Wochen und days seit dem ersten day der letzten Periode. Schreibweise: SSW 12+3 = 12 vollendete Wochen und 3 days = Sie sind in der 13. SSW. 3. Trimester zuordnen: 1. Trimester (SSW 1-12): Organanlage, Uebelkeit haeufig. 2. Trimester (SSW 13-27): Babybewegungen spuerbar, stabilere Phase. 3. Trimester (SSW 28-40): Wachstum, Vorbereitung auf Geburt. 4. Errechneten Termin anzeigen: Der ET wird automatisch calculates (280 days nach letzter Periode). 5. Verbleibende days ablesen: Der Rechner zeigt, wie viele days bis zum ET verbleiben. 6. Mutterschutz planen: Der Mutterschutz beginnt 6 Wochen vor dem ET und endet 8 Wochen nach der Geburt.
Calculation Example
Letzte Periode: 1. Januar 2026, heutiges Datum: 15. April 2026. Vergangene days: 104. SSW: 104 / 7 = 14+6 (Sie sind in der 15. SSW). Verbleibend: 176 days bis ET (8. Oktober).
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