Calculate Working Days Between Two Dates Calculate the number of business (working) days between two dates, excluding weekends.

The calculator iterates through each day from the start to end date using a while loop, incrementing by one day. For each day, it checks the day of week using getDay() (0 = Sunday, 6 = Saturday) and classifies it as a weekend day or business day based on the user's configuration. This brute-force approach is O(n) where n is the number of days, but it's perfectly efficient for date ranges up to decades. For very large ranges, a mathematical optimization could compute complete weeks and handle only the partial week at each end, but the iteration approach is simpler and handles edge cases naturally. The tool sorts the dates automatically if the end date precedes the start date, ensuring consistent results regardless of input order.