Ovulation Calculator

Calculate your fertile window and estimated ovulation date based on your menstrual cycle length.

📋 Data Entry

First day of last menstrual period

Cycle Length (days)

Period Duration (days)

📄 Result

Result

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⚠️ This calculator is for informational purposes only and is NOT a contraceptive method. Consult a healthcare provider for family planning.

About this calculator

Ovulation typically occurs 14 days before the next period, regardless of cycle length. The fertile window begins 5 days before ovulation (sperm can survive up to 5 days) and ends 1 day after. Irregular cycles make this calculation less precise.

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