Estimate Your Ovulation Date
What Is This Tool Used For?
This calculator helps estimate your ovulation day and identify your fertile window — the days you're most likely to conceive. It uses the calendar method based on your menstrual cycle, not hormonal testing or ovulation kits.
Who Can Use This Calculator?
- Anyone trying to conceive naturally.
- People who know the start date of their last period and their average cycle length.
- Anyone looking to understand or track their menstrual cycle and fertility signs better.
What You Will Need
- The first day of your last menstrual period (LMP).
- Your average cycle length — the number of days from the first day of one period to the first day of the next.
- (Optional) Your typical luteal phase length.
Your Result & What It Means
Once calculated, your result will include:
- Your estimated ovulation date.
- Your fertile window (most fertile days).
Disclaimer: This tool gives an estimated ovulation date based on average cycles. It doesn’t track real-time signs like body temperature or cervical mucus and is not a substitute for medical advice. For irregular cycles or fertility concerns, please speak with a healthcare provider.