This calculator uses the calendar method based on the assumption that the luteal phase (time from ovulation to next period) is exactly 14 days.
Formula: Ovulation = (Next Period) - 14 days
The fertility window spans 5 days before ovulation plus the day of ovulation itself, providing a 6-day window where conception is most likely.
Calculate your estimated ovulation date, fertile window, and next period based on your menstrual cycle. Precise tracking for family planning.
Typical cycle is between 21 and 45 days (Default: 28)
IMPORTANT: This tool provides estimates based on averages and should NOT be used as a method of birth control or for definitive medical advice. Consult a healthcare professional for accurate planning.
Results are estimates based on standard models. Please verify critical data before taking action. Terms of Use
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