Conception & Ovulation Date Calculator
Calculate the estimated date of conception, fertile window, and embryo implantation timeline based on your expected due date or the first day of your last menstrual period (LMP). Supports customizable cycle lengths from 21 to 35 days.
Estimated Due Date
Biologically, human gestation averages 266 days (38 weeks) from the moment of conception, which aligns with 280 days from LMP in a standard 28-day cycle.
Fertility & Implantation Milestones
• Ovulation Window: Conception occurs within 12 to 24 hours of the egg release, though viable intercourse can occur up to 5 days prior due to sperm survival.
• Blastocyst Implantation: The fertilized egg travels down the fallopian tube and implants into the uterine lining 6 to 12 days following fertilization, initiating hCG hormone production.
How to Use Conception & Ovulation Date Calculator
Choose Calculation Method
Select either Expected Due Date or Last Menstrual Period (LMP).
Enter Dates & Cycle Length
Pick your date and specify your average menstrual cycle length (default 28 days).
Review Timeline
Inspect the most probable conception date, fertile intercourse range, and embryo implantation window.
Frequently Asked Questions
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