Ovulation Calculator
Calculate your most fertile days to help you plan or avoid pregnancy.
Calculate Your Ovulation
Your Fertile Window
How ovulation is calculated
Ovulation typically happens 14 days before your next period. Your fertile window is 5 days before ovulation plus the day of ovulation.
First day of last period + (cycle length - 14)Fertile window:
5 days before ovulation to 1 day afterBest days: 2-3 days before ovulation
Sperm can live up to 5 days, but the egg only survives 12-24 hours after ovulation.
FAQs
What is ovulation?
Ovulation is when your ovary releases an egg. This usually happens once per menstrual cycle.
When am I most fertile?
The 2-3 days before ovulation are your most fertile. Have intercourse every 1-2 days during your fertile window.
How do I know if I'm ovulating?
Signs include clear stretchy cervical mucus, slight temperature rise, and ovulation pain. Ovulation tests can confirm.
Can I get pregnant outside my fertile window?
It's unlikely but possible. Sperm can survive up to 5 days, and ovulation timing can vary.
What if my cycles are irregular?
This calculator works best with regular cycles. See a doctor if your cycles vary by more than 7 days.