Estimate your most fertile days and ovulation date based on your menstrual cycle.
Ovulation typically occurs about 14 days before the start of your next period. For a 28-day cycle, that's around day 14. For a 32-day cycle, it's around day 18. This calculator uses the standard luteal phase length of 14 days to estimate your ovulation date.
Sperm can survive in the reproductive tract for up to 5 days, and the egg is viable for about 12-24 hours after ovulation. This means the fertile window spans roughly 6 days: the 5 days leading up to ovulation plus ovulation day itself. The highest probability of conception is the day before and day of ovulation.