How Ovulation Calculation Works
1
Cycle Length
Your cycle length is the number of days from the first day of one period to the first day of the next period.
2
Ovulation Timing
Ovulation typically occurs 14 days before your next period, regardless of cycle length.
3
Fertile Window
Your fertile window includes 5 days before ovulation and the day of ovulation itself.
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This calculator runs entirely in your browser. No data is sent to our servers or stored anywhere. Your personal information stays private.
Want More Advanced Tracking?
Try the bloom App
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