Date Calculator

Counting the days between two dates by hand is tedious and error-prone, which is exactly the gap this tool fills. Enter a start and end date to see the span between them, or add and subtract a set number of days from a single date. Schedulers lean on it for deadlines and project timelines, and every result also shows how many business days (Monday to Friday) the span contains, so you don't have to trace a finger across a calendar.

Under the hood, the day count is the plain difference between the two dates, so January 1 to January 31 is 30 days, and adding or subtracting moves the date by that many calendar days, with month lengths and leap years handled by the calendar. The business-day figure walks the range one day at a time, starting the day after the earlier date and including the later one, and skips every Saturday and Sunday. Add/Subtract always moves by calendar days; to find a date a set number of business days away, adjust the number of days until the Business Days line reaches your target.

One caveat worth flagging: the tool subtracts weekends but has no knowledge of public holidays, so a Thanksgiving or July 4th will still be counted as a working day. Cross-reference your local holiday calendar and nudge the final date accordingly. It also helps to be clear on whether a given range is meant to count both endpoints or just one, since the two conventions produce results that differ by a day.