I need to calculate the difference in hours between two dates and times. For
example the difference in hours between 11:25 on 23/07/2004 and 18:00 on
06/08/2004? The dates and times have already been determined by the start and
end of a particular event. Thanks,

Let's say the 23/07/2004 date is in A1 and the 06/08/2004 date is in B1

C1 =(B1-A1)*24 gets time in hours. Ensure that C1 is formatted to say
NUMBER with 2 decimal places.

"Robin CSM002" wrote:

I need to calculate the difference in hours between two dates and times. For
example the difference in hours between 11:25 on 23/07/2004 and 18:00 on
06/08/2004? The dates and times have already been determined by the start and
end of a particular event. Thanks,

One way:

=ROUND((A2-A1)*24,0)

where A1 has your start date/time and A2 has your end date/time. Since
XL stores times as fractional days, multiplying integral plus fractional
days by 24 gives hours.

In article ,
Robin CSM002 <Robin wrote:

I need to calculate the difference in hours between two dates and times. For
example the difference in hours between 11:25 on 23/07/2004 and 18:00 on
06/08/2004? The dates and times have already been determined by the start and
end of a particular event. Thanks,

Calculating Duration Between Two Dates and Times in Excel

Sure, calculating the duration between two dates and times in Excel is easy. You can use the built-in function called "DATEDIF" to calculate the difference between two dates in various units, including hours.

Here's how you can do it:

1. Enter the start date and time in one cell, and the end date and time in another cell. Make sure to format the cells as "Date" and "Time" respectively.
2. Subtract the start date and time from the end date and time to get the total duration in days and fractions of a day. For example, if the start date and time are in cell A1 and the end date and time are in cell B1, you can use the formula "=B1-A1" to get the duration in days.
3. Multiply the result by 24 to convert the duration from days to hours. For example, if the duration in days is in cell C1, you can use the formula "=C1*24" to get the duration in hours.

That's it! You should now have the duration in hours between the two dates and times.