Ovulation is the release of a mature egg from the ovary, typically occurring about 14 days after the first day of a woman’s last menstrual period (LMP) for a standard 28‑day cycle.
The fertile window surrounds ovulation because sperm can survive up to five days in the female reproductive tract, and the egg remains viable for roughly 24 hours after release. Therefore, intercourse from five days before ovulation through one day after maximizes the chance of conception.
By entering the LMP and the individual’s average cycle length, the calculator predicts the ovulation day and highlights the six‑day fertility window, helping couples plan intercourse for optimal timing.
Fertility Window = range of dates (‑5 to +1) around ovulation when conception is most likely
How do I use the Ovulation & Fertility Window Calculator?
What is the typical length of a woman's menstrual cycle?
How long does sperm survive in the female reproductive tract?
For how long is an egg viable after ovulation?
What factors can affect ovulation timing?
Can the calculator account for irregular menstrual cycles?
How accurate is this calculator in predicting ovulation?
Results are for informational purposes only and do not constitute professional advice.