Get work hours between dates and times
To calculate total work hours between two dates and times, you can use a formula based on the NETWORKDAYS function. In the example shown, E5 contains this formula:
where "lower" is the named range H5 and "upper" is the named range H6.
How this formula works
This formula calculates total working hours between two dates and times, that occur between a "lower" and "upper" time. In the example shown, the lower time is 9:00 AM and the upper time is 5:00 PM. These appear in the formula as the named ranges "lower" and "upper".
The logic of the formula is to calculate all possible working hours between the start and end dates, inclusive, then back out any hours on the start date that occur between the start time and lower time, and any hours on the end date that occur between the end time and the upper time.
The square brackets stop Excel from rolling over when hours are greater than 24. In other words, they make it possible to display hours greater than 24. If you need a decimal value for hours, you can multiply the result by 24 and format as a regular number.
If start and end times will always occur between lower and upper times, you can use a simpler version of this formula:
No start time and end time
To calculate total work hours between two dates, assuming all days are full workdays, you can use an even simpler formula:
See explanation here for details.