Ovulation Calculator & Fertile Days
Discover your ovulation day, fertile window, and next period in seconds.
Ovulation day
Mon, Sep 7
Fertile window start
Wed, Sep 2
Fertile window end
Tue, Sep 8
Estimate for regular cycles. Not a contraceptive method.
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Frequently asked questions
How do I know when I ovulate?
Our ovulation calculator estimates your ovulation day based on the first day of your last period and your average cycle length. It helps you identify your most fertile days and when to take a pregnancy test.
What is the fertile window?
The fertile window is the six days leading up to and including ovulation. Sperm can survive up to five days, so pregnancy is most likely when intercourse occurs during these days.
How accurate is this calculator?
This calculator provides an estimate based on a regular 28-day cycle. Your actual ovulation day may vary, so use it as a guide and consider tracking other symptoms for better accuracy.
Can this calculator determine my baby's gender?
No, this calculator only estimates ovulation and fertile days. It cannot determine the sex of a baby. The timing of intercourse may play a role, but there’s no scientific guarantee.
What Is Ovulation?
Ovulation is the process where a mature egg is released from an ovary. This typically happens once a month, about 12 to 14 days before your next period. Knowing your ovulation day is key to understanding your fertility and planning a pregnancy.
How to Use the Ovulation Calculator
To estimate your fertile days, enter the first day of your last menstrual period and your average cycle length. The calculator will show your estimated ovulation day, fertile window, and next period date. It’s a simple and fast tool for tracking your monthly cycle.
Understanding Your Fertile Window
Your fertile window includes the five days before ovulation and the day of ovulation itself. Having intercourse during this period gives you the highest chance of conception. Sperm can live inside the female body for up to five days, making these days crucial.