Understanding Your Fertile Window
Ovulation is the release of an egg from the ovary, typically occurring 14 days before your next expected period. An egg survives for 12–24 hours after release, but sperm can live in the reproductive tract for up to 5 days — creating a fertile window of approximately 6 days.
Fertile Window
The ~6 days when pregnancy is possible: 5 days before ovulation and the day of ovulation itself.
Peak Fertility
The 2–3 days immediately before and including ovulation day offer the highest chance of conception.
Luteal Phase
The phase after ovulation until your next period. Usually 12–16 days. Consistent between cycles.
Cycle Length
A normal cycle is 21–35 days. Shorter or longer cycles affect when ovulation occurs.
How to Improve Accuracy
This calculator uses the standard formula based on average cycle length. For more accuracy, track basal body temperature (BBT), use ovulation predictor kits (OPKs), or monitor cervical mucus changes — all of which detect actual ovulation rather than predicting it.