Fertility Calculator

Ovulation Calculator

Find your fertile window and predicted ovulation day based on your menstrual cycle. Knowing your ovulation timing is the single most important factor in timing intercourse for conception. Enter your cycle details below for an instant, personalized forecast.

Your Cycle Details

The first day of bleeding in your most recent cycle

From first day of one period to first day of the next

Days from ovulation to next period, typically 14

Not sure of your luteal phase? Leave it at 14, the average for most women.

Note: This calculator provides estimates only. For medical concerns about fertility, consult a reproductive endocrinologist.

Discover Your Fertile Days

Enter your cycle details on the left to see your personalized fertile window and ovulation day prediction.

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