When Is My Due Date Calendar. Find out your baby’s estimated date of arrival with the pregnancy due date calculator! This means your cycle is between 24 and 38 days long, and it’s close to the same length every time.
Your due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period (assuming a 28 day cycle). Only 1 in 20 babies are born on their.