When Do You Ovulate?
Ovulation — the release of an egg from the ovary — usually occurs about 14 days before your next period. For a woman with a 28-day cycle, that's day 14. For shorter or longer cycles, it shifts accordingly. Our calculator uses your LMP and average cycle length to predict ovulation day and your fertile window.
The Fertile Window
Sperm can survive up to 5 days in the reproductive tract, and the egg lives about 24 hours after ovulation. That creates a fertile window of roughly 6 days — the 5 days before ovulation plus ovulation day. This is the best time to try to conceive.
Signs of Ovulation
- Changes in cervical mucus (clear, stretchy, like egg whites)
- Slight rise in basal body temperature (BBT)
- Mild one-sided pelvic pain (mittelschmerz)
- Increased libido
- Positive ovulation predictor kit (OPK)
Accuracy Note
Calendar-based predictions are estimates. For the most accurate tracking, combine this calculator with ovulation predictor kits, basal body temperature charting, or fertility apps. Consult your OB-GYN if you have irregular cycles or have been trying to conceive for over a year.