Enter the first day of your last period and your average cycle length to see your estimated fertile window, ovulation day, and next period.
This tool should not be used alone to prevent pregnancy. Results are estimates — actual ovulation can vary, especially with irregular cycles.
Ovulation typically occurs about 14 days before your next period starts, regardless of your total cycle length. So for a 28-day cycle, ovulation is usually around day 14; for a 32-day cycle, closer to day 18. Your fertile window is generally the 5 days before ovulation plus the day of ovulation itself, since sperm can survive up to 5 days in the body while the egg survives only 12-24 hours after release.
This calculator works best for regular cycles (21-35 days). If your cycles vary significantly month to month, this estimate will be less reliable — tracking basal body temperature or using an ovulation predictor kit over a few cycles will give you a clearer picture. If you've been trying to conceive for a while without success, it's worth discussing with your doctor.
BabyQuil keeps your cycle, due date, and pregnancy records together in one place.
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