Last updated: March 2, 2026 by Maria Gonzalez

Track Your Menstrual Cycle

Formula

Next Period = Cycle Length - Days Since Last;
Ovulation = Cycle Length - 14 days

Understanding your menstrual cycle helps with family planning, health monitoring, and recognizing irregularities. The average cycle is 28 days, but normal cycles range from 21 to 45 days.

Ovulation typically occurs about 14 days before the next period. The fertile window spans approximately 5 days before ovulation through 1 day after.

Common use cases:

  • Family planning and fertility awareness
  • Tracking menstrual health patterns
  • Preparing for upcoming periods

Frequently Asked Questions

MG

Maria Gonzalez

Registered Dietitian, RD, MPH

Maria is a Registered Dietitian with a Master's in Public Health. She focuses on evidence-based nutrition assessment tools including BMI, calorie calculations, and body composition analysis.

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