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Ovulation Calculator

Determine your most fertile days and increase your chance of conceiving.

When did your last period begin?

Please enter a valid date.

What is your average cycle length?

Start with the first day of one period and count right up to the day before the first day of your next period. Count the first day of bleeding or spotting as day one. The average cycle length is 28 days, but can range anywhere from 20 to 45 days.

Your best days to conceive are


Your likely due date would be

Other future fertile days: