Ovulation Formula: Ovulation Date = ~2 weeks before your period

Ovulation Definition The Ovulation Calculator will calculate your likely ovulation date if you enter in the first day of your last period and your average menstrual cycle length. Also, try out the Due Date Calculator and the Pregnancy Calculator.

How to Calculate Ovulation Let's be honest - sometimes the best ovulation calculator is the one that is easy to use and doesn't require us to even know what the ovulation formula is in the first place! But if you want to know the exact formula for calculating ovulation then please check out the "Formula" box above.