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Ovulation Calculator


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The length of your cycle can vary every month. The ovulation calculator can determine your cycle’s length by counting the days from the first day of your period up to, but not including, the first day of your next period. The average woman’s menstrual cycle lasts about 28 days but it is perfectly normal for your cycle to last anywhere from 24 to 34 days.


On average, ovulation occurs 14 days before the start of your period. However, it is normal for a woman to ovulate anywhere from 12 to 18 days before menstruation. When trying to get pregnant it can be helpful to keep a menstrual cycle and ovulation calendar. The ovulation calculator above will give you an indication of your fertility window based on the length of your cycle. Day one of your cycle is the first day of menstruation; this is the first day that you bleed during your period. Please remember that this ovulation calculator is just a guide and to determine a precise ovulation date we recommend talking to one of our Fertility Specialists.