When is a woman the most fertile during her cycle?

Answer 1

A woman is most fertile during ovulation - which is typically two weeks before menstruation. A woman is also fertile up to a week leading up to ovulation when there is fertile quality cervical mucus present, this can keep sperm alive in the vagina for up to a week by which time the woman may ovulate. Unless you use Fertility Awareness Method you can't know when you're fertile.

Answer 2

while ovulating and a few days before.