The Ovulation Date Calculator is greatly used for people who plan to get pregnant. By using the calculator, you are easy to get your ovulation period. Conceive during your ovulation period could increase the chance of getting pregnant. The simple way to calculate your ovulatory date is to count back 14 days from your next period. After getting the date, add five days before and four days after you will get your 10-day ovulation period. As it's easy to get pregnant during these ten days, the period is also called fertile days or dangerous days.

Following is our ovulation period calculator based on the date of your last period. Please enter the following information and then click 'Calculate' to get your fertile days in the calendar. Your next Ovulatory periods will be marked with the red.

Please note that a regular menstrual cycle length is between 26 and 35 days and lasts from 3 to 8 days. If your period is irregular, this will not fit you.

There are many ways to test your ovulation period. The tool we offer here is calculated based on your menstrual cycle. If your period is not regular, you are suggested to use other ways such as monitoring your body's temperature (In general, if you find your temperature is not normal and increase especially in the morning after you get up, it hints your ovulation period is coming.), observing a sample of cervical mucus (If it's slippery, clear and stretchy just like the consistency of egg whites, you are more likely fertile), using the ovulation test paper or other ovulation prediction kits.