Ovulation Calculator
Calculate your fertile window and estimated ovulation date based on your menstrual cycle.
Next Ovulation Date
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Fertile Window
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Next Period (est.)
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Luteal Phase
14 days (average)
How to Use the Ovulation Calculator
- Enter your last period date: Provide the first day of your most recent menstrual period.
- Set your cycle length: Enter your average menstrual cycle length (default is 28 days).
- View results: See your estimated ovulation date, fertile window, and upcoming cycles.
How Ovulation is Calculated
Ovulation typically occurs about 14 days before the start of your next period. The fertile window spans approximately 5 days before ovulation and 1 day after, as sperm can survive up to 5 days in the reproductive tract.
Frequently Asked Questions
When am I most fertile?
You are most fertile in the 2-3 days leading up to and including the day of ovulation. This is when conception is most likely to occur.
How accurate is this calculator?
This calculator provides estimates based on average cycle patterns. For more accurate tracking, consider using ovulation predictor kits (OPKs) or basal body temperature monitoring.