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Conception Date Calculator
Estimate a central conception date from a clinically estimated due date.
- Central conception estimate
- July 15, 2026
How the calculation works
Central conception estimate = estimated due date − 266 days.
Inputs
- Estimated due date
Calculation details
Dates are approximate and do not confirm pregnancy. A clinician establishes gestational dating using history and ultrasound; IVF requires separate dating.
This cannot identify the exact date of intercourse or establish paternity. Ovulation and fertilization may differ from the calendar estimate.
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Updated: 2026-10-02