Calculator

Ovulation Calculator

Estimate ovulation date, fertile window, next period, and test date from cycle length and luteal phase.

How it works

Method

The calculator applies the formula shown in the result cards and updates instantly as values change.

Assumptions

Editable rates, odds, values, and percentages should match your current source, supplier, or platform data.

Privacy

Calculations run in your browser. No extra API request is needed for these estimates.