On which day of the 28-day human ovarian cycle, does ovulation occur?

The human ovarian cycle is typically 28 days long, though this can vary depending on the individual. 

Ovulation usually occurs around day 14 of the cycle, but this can vary depending on a number of factors such as age, hormonal imbalances, and overall health.

Ovulation timing can be influenced by a variety of factors, including stress, illness, and changes in body weight, and can vary from cycle to cycle. As a result, predicting the exact day of ovulation can be difficult. 

Tracking physical ovulation signs, such as changes in basal body temperature or cervical mucus, or using ovulation prediction kits, can help predict the approximate time of ovulation.