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Period Calculator

Track your menstrual cycle, predict your next period, and identify your fertile window and ovulation day.

Typical: 21–35 days
Typical: 3–7 days

Understanding Your Cycle

🩸 Menstrual Phase (Days 1–5)

The uterine lining sheds. This is when bleeding occurs, typically lasting 3–7 days.

🌱 Follicular Phase (Days 1–13)

Hormones stimulate egg development in the ovaries. Estrogen rises, thickening the uterine lining.

🥚 Ovulation (Day ~14)

A mature egg is released. This is the most fertile time — the egg survives ~24 hours.

🌙 Luteal Phase (Days 15–28)

Progesterone rises to support potential pregnancy. If no implantation occurs, hormone levels drop and the cycle restarts.

⚕️ Disclaimer: This calculator provides estimates based on average cycle data. It is not a substitute for medical advice and should not be used as a contraceptive method. Consult your healthcare provider for personalized guidance.