Ovulation calculator

If you're trying to get pregnant, it's helpful to know when you ovulate. Ovulation is when your body releases an egg. This calculator can help you pinpoint your most fertile period—the days just before and after you ovulate. To calculate your fertile time, it helps to know length of your menstrual cycle. You can determine the number of days by counting from the first day of your period to the last day before your next period starts. The average number of days in a woman's cycle is 28, but it's not unusual for women to have longer or shorter periods.

Use the drop down menu to select # of days

Number of Days in Cycle Ovulation Day (Counting from First Day of Cycle)


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