The Ovulation Calculator helps calculate when you are most likely to be fertile. By tracking your period month to month, you can provide greater accuracy to when you are ovulating.
Enter the first day of your last period and how long your cycle usually lasts (between 20 and 45 days). This calculator will show you the best days to have sex that could lead to pregnancy – so you can mark your calendar. Ovulation lasts for 12 to 48 hours, but you are potentially fertile for up to seven days. This is because sperm can survive up to 5 days in the female reproductive track.
Already pregnant? Visit the Pregnancy Calculator.