Conception Calculator
Last Menstrual Period
How It Works
- LMP Mode: Ovulation estimated at LMP + (cycle length − luteal phase). Fertile window = 5 days before to 1 day after ovulation.
- Due Date Mode: Conception estimated 266 days before EDD. Ovulation estimated 14 days after conception.
- Ovulation Test Mode: Ovulation estimated 24–36 hours after positive LH surge. Fertile window surrounds this estimate.
- Known Conception: Due date calculated as conception + 266 days. Ideal for IVF/IUI/confirmed dates.