Ovulation Calculator
Calculate ovulation window and fertile days.
How to Do It Manually
Ovulation typically occurs 14 days before the start of your next period. Track your cycle length and count forward from the first day of your period.
Ovulation Date ≈ First Day of Period + (Cycle Length − 14) days
- Note the first day of your period (day 1).
- Count your average cycle length (e.g., 28 days).
- Subtract 14 from the cycle length.
- Count that many days forward from day 1 to find your estimated ovulation date.
Frequently Asked Questions
Can ovulation be predicted exactly?
No, ovulation timing varies. This calculator provides an estimate; ovulation predictor kits are more accurate.
What's the fertile window?
You're most fertile 5 days before and 1 day after ovulation (6-day window).