Ovulation Calculator
Estimate when you ovulate and your most fertile days, based on your last period and average cycle length.
Show solution steps
What is the Ovulation Calculator?
An ovulation calculator predicts the day an egg is released and the surrounding fertile window — the days when conception is most likely.
How to Calculate
Ovulation typically happens about 14 days before your next period. The fertile window spans roughly the 5 days before ovulation plus ovulation day.
Formula
Ovulation ≈ next period date − 14 days
How to Use
- Enter your details in the fields above.
- The result updates instantly as you type.
- Use Copy, Print or Download PDF to save your result.
Frequently Asked Questions
How reliable is this?
It's an estimate based on a regular cycle. Ovulation timing varies, so combine it with other signs (or medical guidance) if you're tracking closely.
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