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Calculate Your Most Fertile Days

Maximize your chances of conceiving by predicting your ovulation date and fertile window for the next 3 months. Fast, free, and 100% private browser tool.

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About Calculate Your Most Fertile Days

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1

Last Period

Enter the first day of your last menstrual period (LMP).

2

Cycle Length

Input your average cycle length (days between periods).

3

View Calendar

See your predicted ovulation dates and fertile windows.

Knowing when you ovulate is key to getting pregnant. Our Ovulation Calculator estimates your most fertile days by tracking your menstrual cycle. It provides a detailed calendar of your likely ovulation dates and fertile windows for the upcoming months.

Key Features

3-Month Forecast

Predicts ovulation and fertile windows for your next 3 menstrual cycles.

Fertile Window

Highlights the 6-day period (5 days before + ovulation day) when conception is most likely.

Cycle Adjustments

Works for various cycle lengths, from short (21 days) to long (40 days).

Frequently Asked Questions

Ovulation typically occurs about 14 days before your NEXT period starts, regardless of cycle length.

Sperm can survive for up to 5 days inside the body, so your fertile window includes the 5 days before ovulation plus the day of ovulation itself.

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