Time Duration Calculator
Measure the exact interval between two dates and times, isolate Monday-through-Friday working business days, and convert into total hours and minutes.
Calendar Mechanics & Business Day Calculations
Inclusive vs. Exclusive Days
When counting days between Monday and Wednesday, an exclusive calculation returns 2 days (Tuesday and Wednesday), representing elapsed span.
For event planning, payroll, and work assignments, inclusive counting is often preferred (counting Monday, Tuesday, and Wednesday as 3 working days).
Leap Years & Month Variations
Under the Gregorian calendar, a year is a leap year if divisible by 4, except century years unless also divisible by 400 (e.g. 2000 was a leap year, 1900 was not).
Because months range from 28 to 31 days, calendar durations require dynamic borrowing from previous month lengths rather than static 30-day approximations.
ISO-8601 Duration Format
Software APIs represent durations using the international standard ISO-8601 designator:
For example, P3DT4H30M specifies a precise span of 3 days, 4 hours, and 30 minutes.