What is the number for a "Baker's Dozen"?

A "Baker's Dozen" refers to a quantity of 13 items. The term originated from the practice of bakers who, in medieval times, would include an extra item when selling a dozen baked goods to avoid penalties for selling underweight bread. This custom ensures that customers received a full measure, thus the phrase has become widely recognized to denote the number 13 instead of the standard dozen, which is 12.