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CalcWolf Pregnancy Empfaengnisdatum-Rechner
Pregnancy

When Did Conception Occur?

Calculate the probable conception date from your due date or last menstrual period.

📅 Updated April 2026 Formula verified 📖 4 min read 🆓 Free · No sign-up

Berechnung

Empfaengnis = Geburtstermin minus 266 Tage. Oder: DUM + 14 Tage (±3-5 Tage). Die Befruchtung erfolgt typisch 12-24 Stunden nach dem Eisprung, aber Spermien ueberleben bis zu 5 Tage — das Empfaengnisdatum ist immer eine Schaetzung.

Genauigkeit

Ultraschall im 1. Trimester (7-8 Wochen): ±3-5 Tage. Kalenderberechnung: ±7-10 Tage. Der Frauenarzt kann die genaueste Schaetzung geben.

⚡ CalcWolf Insight

First trimester ultrasound (6-9 weeks) is the most accurate method for determining gestational age, accurate to within 3-5 days. After the first trimester, accuracy drops to 1-2 weeks. If your ultrasound date and LMP date disagree by more than 7 days, the ultrasound date is used for the due date.

Frequently asked questions
Wie genau?
±5-7 Tage. Nur bei IVF/ICSI ist das exakte Datum bekannt.
Kann der Frauenarzt das bestimmen?
Annaehernd — Ultraschall im 1. Trimester gibt die beste Schaetzung.
✓ Math logic verified against primary sources → See our verification process
Kevin Glover
Founder, CalcWolf · GLVTS · Blickr
All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →
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