How fast can a woman ovulate after her period on a usual 28 day cycle that lasts 5-6 days ?

Ovulation: Ovulation can occur any time during a monthly cycle, from day one onwards. However, the most common time to ovulate is around day 14. You can tell when ovulation occurred, since it happens 12-16 days prior to the period. However, this is only helpful in retrospect.

Ovulation: As soon as 5th to 7th day although most commonly around 11-13th.