Ovulation Calculator

Free Ovulation Calculator

Find your most fertile days and maximize your chances of conceiving. Trusted by women in over 150 countries.

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Your Next Fertile Window

Your Cycle Map

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🔮 Get AI-Powered Ovulation Predictions

This calculator uses standard cycle math. The Ovuloom app uses AI + wearable data for significantly more accurate ovulation detection.

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How Does Ovulation Work?

Ovulation is the release of a mature egg from one of your ovaries. It typically lasts 12-24 hours and is the only time during your cycle when conception can occur. Understanding your ovulation timing is crucial whether you're trying to conceive or avoid pregnancy.

How This Calculator Works

Our ovulation calculator uses the calendar method: ovulation typically occurs 14 days before your next expected period (the luteal phase). For a 28-day cycle, that's day 14. For a 30-day cycle, it's day 16. We calculate your 6-day fertile window (5 days before ovulation + ovulation day) because sperm can survive up to 5 days.

Signs of Ovulation

Tips to Maximize Conception

Trusted by Women Worldwide

Women in over 150 cities use Ovuloom's ovulation calculator and fertility tools to plan their families.

Frequently Asked Questions

Ovulation typically occurs about 14 days before your next period. For a 28-day cycle, this means around day 14. For longer or shorter cycles, ovulation shifts accordingly. The Ovuloom app uses AI to predict your exact ovulation date based on your unique cycle patterns.

The fertile window is the 6-day period ending on ovulation day. Sperm can survive up to 5 days in the reproductive tract, so the days before ovulation are also fertile. Peak fertility is the 2 days before and including ovulation day.

Confirm ovulation with BBT tracking (temperature rises 0.5-1°F after ovulation), OPKs (detect LH surge 24-36 hours before), cervical mucus observation, or the Ovuloom app's AI analysis.

This calculator works best with regular cycles. For irregular cycles (varying by 7+ days), predictions may be less accurate. The Ovuloom app uses AI designed for irregular cycles, including PCOS, learning your unique patterns for better accuracy.

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