Typically about 14 days before your next period — cycle length minus luteal phase. On a 28-day cycle with a 14-day luteal phase, ovulation often falls around day 14, but shifting cycle or luteal length moves that day earlier or later. This is an estimate, not a diagnosis.

What is the fertile window?

Sperm can survive several days in the reproductive tract. We show roughly five days before ovulation through one day after — about a six- to seven-day window when conception is more likely. Calendar methods are less reliable with irregular cycles, PCOS, or recent hormonal contraception.

28-day cycle ovulation?

Ovulation often lands around day 14 on a 28-day cycle with a default 14-day luteal phase, but individual luteal length varies. Enter your typical cycle length and last period start for a personalized estimate. Tracking basal body temperature or ovulation tests refines timing.

Predictions degrade when cycles vary widely month to month or after hormonal shifts. Consult a healthcare provider for persistent irregularity. Calendar estimates are educational only — not contraception, diagnosis, or treatment. Symptoms and clinical advice always override app-style fertile-window calculations.

Is this medical advice?

No. These are educational estimates for cycle awareness and planning discussions with a clinician — not for contraception, fertility treatment, or diagnosis. Irregular cycles, PCOS, and recent hormonal contraception reduce reliability compared with home ovulation test kits or medical monitoring.