Health
Ovulation Calculator
Estimate fertile window from cycle start date.
Inputs
Ovulation Calculator
Result
Estimated ovulation
Tue Sep 29 2026
- Fertile window
- Thu Sep 24 2026 → Tue Sep 29 2026
Estimating the fertile window
In a typical 28-day cycle, ovulation happens around day 14 and the fertile window spans roughly the 5 days before ovulation plus the day itself. Cycle length varies, so results are estimates — track basal temperature or use ovulation strips for higher confidence.
If you're already expecting
Move on to the Pregnancy Calculator for the estimated due date and trimester breakdown.
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