Calculate your period calendar

The menstrual cycle – is a cyclical process occurring every month in a woman's body, and helping prepare the body for a possible pregnancy. In simple words, this is the interval from the beginning of one menstrual period to the next. The calendar is often used to calculate the days of the menstrual period or the most fertile days (with the chance of getting pregnant).

How to calculate menstrual cycle?

The first day of the cycle is the first day of the menstrual period, and the last day is the day before the next period. Usually, the cycle ranges from 21 to 35 days, and the menstrual period lasts from 3 to 7 days. But these indicators can depend on many factors, from age to genetics. Also, with an ideal cycle (28 days), ovulation occurs around day 14, and during this period a woman has a very high chance of becoming pregnant. To calculate the menstrual cycle, you need to know the day of the beginning and end of the last menstruation, the duration of the menstrual period.

Specify the first day of the last

Specify cycle duration

Duration of menstruation


High probability of conception


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