Ovulation Calculator
Ovulation day and fertile window for your cycle.
Result
ResultEnter your LMP date
Ovulation Calculator — FAQs
When is the fertile window?
The 5 days before ovulation plus ovulation day — sperm survive ~5 days, the egg ~24 hours. Ovulation is typically 14 days before the next period, not mid-cycle for irregular cycles.
When am I most fertile?
The ~5 days before ovulation plus ovulation day — roughly day 10–15 of a 28-day cycle, tracked from your LMP.
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